The Journal of the Institute of Metals, Vol. 53, No. 3

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(1)1933. No. 3. THE JOURNAL OF THE INSTITUTE OF METALS VOLUME LI 11. METALLURGICAL ABSTRACTS A ND. INDEX TO VOLUMES LI, W, and LIII OF TH E. JOURNAL E D ITE D BY. G. SHAW SCOTT, M.Sc. S ecretary. The. right of Publication and of Translation is Reserved. The. Institute of Metals is not responsible either for the statements made or for the opinions expressed in the following pages. LONDON PUBLISHED BY THE INSTITUTE OF METALS 3G VICTO RIA ST R E E T , LONDON, S.W .l 1933. Copyright]. [Entered at Stationers' Hall.

(2) £79/33/ s.

(3) ABSTRACTORS AND R EV IEW ERS N . A g e e w , M et.Eng. Professor J . H . A n d r e w , D .S c . Professor C. 0 . B a n n is t e r , M .Eng., A.R.S.M ., F.I.C . Colonel N. T. B e l a ie w , C.B . B . B l u m e n t h a l , D r.-Ing.. C a p tain B . B r a n d t . J . C. C h a sto n , B.Se., A.R.S.M . R . B. D e e l e y , B.Sc., A.R.S.M . J . W . D o n a ld so n , D .Sc., A.I.C. C o n sta n ce F . E lam , D.Sc., M.A. H . J . T. E l u n g h a m , Ph.D ., A .R.C.S., A.I.C. W. E n g e l , Dr.-phil. U. R . E va n s , M.A., D.Sc. R . G e n d e r s , M .B.E., D.M et., F.I.C . H . F . G il l b e , Ph.D ., B.Sc. F rhr. v . G ö l e r , D r.-Ing. R o o sev elt G r if f it h s , M.Sc. J . D. G r o g a n , B.A. D ott. G . G u z zo n i . G. A. H a n k in s , D.Sc., A.R.C.S. M. H a n s e n , D r.-p h il. E. S. H e d g e s , D.Sc., P h.D ., A.I.C. H . W . G. H ig n e t t , B.Sc.Eng., A.I.C. 0 . F . H u d so n , D.Sc., A.R.C.S. W . H u m e -R o t h e r y , M.A., Ph.D . Z. J a siew ic z , M.S. F. J o h n so n , D.Sc. P. S. L e w is , Ph.D ., B.Sc., F.I.C. Professor D r. L. L o sa n a . Professor W . M is .vngyi , D r.-tcchn. W . A. C. N ew m a n , B.Sc., A.R.S.M ., A .R.C.S., F.I.C . E . ÖHMAN. Ing. R . P o s p is il . A. R . P o w e l l . G. D . P r e st o n , B.A. W . P . R e e s , M .S c . P h o e b e M. C. R o u t h , B.Sc. D. N. S h o y k e t , Chem.Eng. C. J . S m it h e l l s , M.C., D.Sc. Professor J . F. S p e n c e r , D.Sc., Ph.D ., F.I.C . H . S u tto n , M.Sc. J . S. G. TnoMAS, D.Sc. E . H . S . VAN SOMEREN, B.Sc. J . H . W a tso n , M.C., Ph.D ., B.Sc., A.R.S.M. J . W e e r t s , D r.-Ing. S. W e r n ic k , Ph.D ., M.Sc. S. V. W il lia m s , B.Sc. A. B. W in t er b o t t o m , M .Sc.Tech., F.I.C . Sf. Z v e o in t z o v , B.A., B.Sc..

(4) S y m b o l s a n d A b b r e v ia t io n s U s e d i n T e x t .. A. Angstrom units. abs. absolute. a.c. alternating current(s). amp. ampère(s). amp.-hr. ampère-hour(s). A.W.G. American wire-gauge. Bé. Baumé. B. & S. Brown & Sharpe (gauge). B.H.P. brake horse-power. B.O.T. Board of Trade. B.th.u. British thermal units. B.T.U. Board of Trade unit. B.W.G. Birmingham -wire-gauge. C. centigrade. cal. calorie(s). c.o. cubic centimetre(s). centigramme(s). egc.g.s. centimetre-gramme-second. cm. centimetrc(s). cm.® square centimetre(s). cm.3 cubic centimotre(s). coeff. coeflicient(8). const. constant(s). c.p. candle-power. C.Ï.U . centigrade thermal units. cwt. hundredweight(s). d. density. d.c. direct currents). decigrammc(s). dgdiam. diameter(s). dm. decimetre(s). dm.2 square decimetre(s). dm.3 cubic decimetrc(s). e.m.f. electromotive force(s) P. Fahrenheit. ft. foot; feet. ft.2 square foot. ft.3 cubic foot. ft.-lb. foot-pound(s). gall. gallon(s). grm. gramme(s). H.-F. high-frequency. H-ion. hydrogen ion. H.P. horse-power. H.P.-hr. horse-power hour(s). hr. hour. hrs. hours. in. inch; inches. square inch. in.2 in.3 cubic inch. in.-lb. inch-pound(s). I.S.W.G. Imperial standard wire-gauge. K. absolute temperature (scale). K.C.U. kilogramme-degree-centigrado heat unit ( = 3-97 B.th.u.). kilogramme(s). kgkg.m. kilogramme-metre(a). km. kiloinetro(s).. km.2 kv. kva. kw. kw.-hr. 1. lb. L.-F. m. m.2 in.3 m.amp. max. mg. mm. mm.2 mm.3 m.ni.f. mu m.v. N. N.T.P. oz. P.C.E. p.d. p.p.m. 11. r.p.m . sp. gr. sq. V. va. w. w.-lir. w.p.c. O ? MM n r // < > <. <. square kilometre. kilovolt(s). kilovolt-ampere(s). kilowatt(s). kilowatt-liour(s). litre(s). pound(s). low-frequency. metre(s). square metre(s). cubic metro(s). milliampirc(s). maximum. milligramme(s). millimetre(s). square millimetre(s). cubic millimetre(s). magnetomotive force(s). millimicron. millivolt(s). normal. normal temperature and pres sure. ounce(s). pyrometric cone equivalent. potential difference. parts per million. Reaumur. revolutions per minute. specific gravity. square. volt(s). volt-ampire(s). watt(s). watt-hour(s). w atts per candle. dcgree(s) (arc or temperature). per cent, wave-length. micron. 1 millionth micron = 0-1 A. ohm. minute of tho arc. second of the arc. A < B denotes th at A is less than B. A > B denotes th at A is greater than B. negative of < ; A <£ B de notes th at A is not less than B. combination of < and = ; A < B denotes that A is equal to or less than B. is not equal to. identically equal to. approximately (or essentially) equal to..

(5) CONTENTS. METALLURGICAL ABSTRACTS. I. II. III. IV. V. VI. VII. VIII. IX. X. XI. XII. XIII. XIV. XV. XVI. XVII. XVIII. XIX. XX. XXI. XXII. XXIII. XXIV.. Properties of Metals, 1, 05, 113, 177, 225, 289, 337, 433, 481, 545, 609, 689. Properties o£ Alloys, 9, 69, 120,181, 232, 294, 343, 435, 489, 548, 610, 694. Structure (Metallography, Macrography, Crystal Structure), 16, 75, 128, 187, 238, 303, 350, 440,497, 554, 628, 700. Corrosion, 19, 77, 131, 193, 241, 307, 355, 442, 499, 555, 631, 703. Protection (other than Electrodeposition), 23, 84, 134, 194, 245, 309, 358, 443, 502, 556, 636, 705. Electrodeposition, 27, 87, 136, 197, 249, 310, 360, 445, 506, 557, 639, 706. Electrometallurgy and Electrochemistry (other than Electrode position and Electro-refining), 32, 92, 137, 199, 256, 314, 362, 449, 512, 560, 642, 709. Refining (including Electro-refining), 32, 92, 139, 199, 257, 314, 363, 450, 513, 562, 643, 709. Analysis, 35, 94, 140, 200, 257, 315, 364, 451, 514, 563, 644, 710. Laboratory Apparatus, Instruments, &c., 37, 96, 142, 202, 261, 322, 371, 454, 515, 566, 649, 711. Physical and Mechanical Testing and Radiology, 38, 97, 143, 202, 262, 323, 373, 455, 516, 567, 651, 711. Pyrometry, 40, 98, 145, 204, 265, 326, 376, 457, 521, 569, 656, 713. Foundry Practice and Appliances, 40, 98, 146, 204, 266, 326, 376, 457, 521, 570, 657, 713. Secondary Metals : Scrap, Residues, &c., 42, 99, 153, 207, 270, 327, 382, 458, 523, 574, 661. Furnaces and Fuels, 44, 99, 154, 207, 271, 328, 382, 458, 523, 575, 661, 716. Refractories and Furnace Materials, 47, 158, 208, 273, 328, 384, 524, 577, 663, 717. Heat-Treatment, 47, 160, 212, 276, 329, 388, 526, 582, 664, 717. Working, 48, 161, 212, 276, 330, 388, 526, 582, 665, 718. Cleaning and Finishing, 52, 164, 216, 278, 393, 527, 584, 668, 719. Joining, 53, 100, 166, 217, 280, 331, 396, 528, 585, 669, 719. Industrial Uses and Applications, 56, 101,168, 282, 331, 406, 459, 529, 590, 675. Miscellaneous, 108, 220, 469, 533, 597, 680. Bibliography, 57, 109, 173, 220, 283, 420, 477, 538, 598, 682. Book Reviews, 60, 111, 176, 223, 286, 335, 426, 478, 540, 603, 684.. INDEX TO VOLS. LI, LTI, LIII OF THE JOURNAL. r.vot:. Subject I n d e x .................................................................................. 721 Name Index . . . . . . . . . 808.

(6) CORRIGENDA 11, line 5. Delete “ ° C.” 70, „ 19.» For “ 7j . MetaUkunde, 1932, 24, 181-184, 207-210 ” read “ Z. MetaUkunde, 1932, 24. 231-233.” 70, „ 18.* For “ 726” read “ 727.” 133, „ 13.* For “ 1932, 495-504 ” read “ 1931, 495-504.” 140, „ 6. For “ A. H. Williams ” read “ H. R. Williams.” 151, „ 6. For “ 1932, 42, 125-126,” read “ 1933, 42, 125-128.” 164, „ 9.» For “ 1933, 33,” read “ 1933, 23.” 175, „ 21.* For “ M. Waehlert ’ ’ read “ M. Waehlert,” 183, „ 23.* For “ 1932, 4 ” read “ 1932, 4. 162-185, 186-203.” 231, „ 15. For “ Superconductivity ” read “ Susceptibility.” 237, „ 3.* Insert “ [In German] ” before “ Investigations.” 247, „ 15. For “ 1932, 50, 481, 670 ” read “ 1932, 50, 482, 670.” 253, „ 5. For “ Seo J., this volume, p. 247 ” read “ this J., 1932, 50, 247.” 277, „ 27. For “ 32, (2), 18-22 ” read “ 23, (2), 1S-22.” 34fi, „ 30. fo r “ 1933 ” read “ 1932.” 349, „ 1. fo r “ Ganneri ” read “ Canneri.” 419, „ 24.* fo r “ 1932, 43, 76 ” read “ 1932, 43, (16), 76.” 444, „ 22.* For “ 1933, 31, 89-98 ” read “ 1933, 31, 89-90.” 470, „ 12 and 13. fo r “ 0. E. Mantcll ” read “ C. L. Mantcll.” 490, „ 3.* For “ Cf. J., this volume, p. 11,” read “ Gf. J., this volume, p. 10.” 515, „ 4. For “ 1932, 4 ” rani “ 1932, 41.” 515, „ 5. For “ K 3Fe(CN), ” read " K 4Fe(CX)e.” 519, „ 30. For “ G rier” read “ Gier.” 538, „ 5.* For “ Bader ” rea<Z “ Baader.” 569, „ 15.* For “ F. II. Schofield ” read “ T. H. Schofield.” 613, „ 17 and 18.* For “ W. C. Burgers ” read “ W. G. Burgers.” 623, „ 9. For “ 1933, 1-9 ” read “ 1933, 1-94.” 624, „ 24. Insert “ IX ” before “ Transformations.” 635, „ 6.* fo r “ Soderburg” read “ Soderberg.” 636, „ 11.* For “ Bergston ” read “ Bengston.” 644, „ 1 For “ Hervey ” read “ Harvey.” 650, ,, 23.* fo r “ 600° 0.” read “ 800° C.” 679, „ 24. For “ 12, 64-65 ” read “ 12, 64-65, 77-78.” 710, „ 17. fo r “ Sargant ” rca<i “ Sarjant.”. .. * From bottom of pago..

(7) METALLURGICAL. ABSTRACT S. (G E N E R A L A N D N O N -F E R R O U S ). 1933. JA N U A R Y. P a rt 1. I.— P R O P E R T IE S O F M ETA LS. A Unique Electrode Potential Characteristic of a Metal, and a Theory for the Mechanism of Electrode Potential [Cadmium]. A. L. McAulay an d E . C. R. Spooner {Proc. Roy. Soc., 1932, [A], 138, 494-501).—F o r concentrations less th an a definite lim it, experim ental results indicate th a t the potential of a cadm ium electrode in an aqueous solution is independent of all changes in the character an d constitution of th e solution. I t is concluded th a t th e electrode p o tential m ust originate in in teraction betw een th e m etal and w ater only. A theory of th is result and three consequences of the theory are briefly dis cussed. The theory contem plates th e form ation of a layer of ions of thickness ab o u t 5 X 10-5 cm. surrounding th e m etal, th e to ta l concentration therein being about 4 x 10-5 grm.-mol. p er litre. The electrode potential of cadm ium in air-free dilute solutions of an y so rt is 0-787 v. against the sa tu ra te d calomel electrode a t 18° C. W hen an electrode is exposed to air, the potential becomes positive and unreproducible. The layer of positive ions surrounding the electrode is more concentrated in this ease, an d to this, and n o t to the form a tion of an im pervious film, th e change of potential is attrib u tab le.—J . S. G. T. The Relaxation Time of Annealed Copper and Aluminium Wires Subjected to Torsional Oscillations. D ank w art Schenk (Z . Physik, 1932, 78, 470—478).— [Note by Abstractor: The relaxation tim e of a m aterial, e.g. of a wire, is related to the dam ping of vibration in th e m aterial. If torsional oscillations of respective frequencies and N„ are characterized by logarithm ic decrem ents I ) i an d D 2 for equal strains, th en the relaxation tim e, 1/It, is given by 1 /R = rr(Dl — D 2)/2(N 1D l — N ,D 2). The relaxation tim e of brass is ab o u t 1/1500 second; its value for D uralum in is about 1/750 second, for E lektron, ab o u t 1/100 second.] The relaxation tim es of copper an d alum inium wires subjected, after annealing, to torsional oscillations are found to depend on th e am plitude of th e oscillations and on th e annealing tem perature. Values of 1/R for copper range from 1/220 to 1/140 second. R esults w ith alum inium w ires were n o t so reproducible as in th e case of copper wires. T his resu lt is probably associated w ith irregularity of the recrystallization process in alum inium , and w ith th e presence of im purities. The results are in terp reted in term s of stru ctu ral changes occurring in th e wires. Torsional oscillations arc accom panied bv m otion w ithin single crystals and motion of th e crystals them selves. R depends on th e relative im portance of these tw o modes of m otion.— J . S. G. T. Null-Point for Charges on Copper and Silver. M. A. Proskum in (Zhum al Fizicheslcoy K h im ii (Journal o f Physical Chemistry), 1932, [W], 3, (1), 91-96).— [In Russian.] Two m ethods are described, based on th e observation of the e.m.f. generated by the change in ionic concentration in solution duo to adsorption on the clean surface of th e metal. Copper is found to have a nullpoint a t — 0-32 v., and silver a t + 0-23 v. against the iV-calomel electrode. Theso values differ m arkedly from th a t found for mercury (— 0-50 v.) by the electrocapillary m ethod. The m ethod of treatm en t of the surfaco has an im p o rtan t influenco on th e null-point.—N . A. The Passivity of Gold. W illiam Jam es S h u tt an d A rth u r W alton (Trans. Faraday Soc., 1932, 28, 740-752).—T he tim e required for th e potential of a passivated gold anode to fall to norm al during spontaneous reactivation in acid chloride solutions has been determ ined u n der conditions which preclude the possibility of direct electrical polarization. The high tem perature coeff. of the VOL. L IU .. B.

(8) 2. A bstracts o f P a p e rs. ra te of recovery suggests th a t th e process of recovery is n o t controlled by simple solution of th e film and diffusion of th e products, b u t b y a chemical reaction. Assum ing th a t the film is a peroxide, to w hich assum ption all th e evidence points, th is reaction would appear to be th e form ation of chlorine and auric oxide from hydrochloric acid and th e peroxide and th e subsequent dissolution of th e auric oxide in th e acid.—A. It. P. Thermal Expansion of Lead. P e te r H id n o rt and W . T. Sweeney (U .S. B ur. Stand. J . Research, 1932, 9, 703-709; Research Paper No. 500).—M easurements have been made on th e linear therm al expansion of 3 sam ples of cast lead betw een room tem perature and 300° C. an d th e results have been correlated w ith d a ta obtained by o th er investigators betw een th e years 1740 and 1931. A curve has been derived w hich shows th e linear therm al expansion of lead between — 253° C. and + 300° C. Average coeff. of expansion for various tem perature ranges between —250° C. and + 3 0 0 ° C. as derived from the expansion curve arc as follow ( x 10-8) : — 250° to -f- 20° C., 25-1; — 200° to + 20° C., 26-5; - 100° to 20° C., 2S-3; + 20° to 60° C., 28-8; 20° to 100° C., 29*1; 20° to 200° C., 30-0; 20° to 300° C., 31-3. A comparison of the indirect results obtained by K opp and M atthiessen w ith th e direct d a ta obtained by other observers indicates th a t lead expands th e sam e in all directions.— S. G. The Chamber Process. XXHI.—Physical and Mechanical Tests of Sheet Lead. M ototaro M atsui and H irondo K ato (Kogyo Kivagaku Zasshi (,/. Soc. Chem. Ind., Japan), 1932, 35, (7), 3 0 4 b - 3 0 6 b ). — [In Japanese, w ith English sum m ary in supplem ental binding.] The lead sheets tested were th e following (trade nam es): (1) T adanac (Canada), technically pure, 99-99% ; (2) B.M. (Burm a), technically pure; (3) Selby (U.S.A.) technically pure, 99-98 + % ; (4) Selby (U.S.A.), lead 95, antim ony 5 % ; (5) unknow n origin, lead 99-299, zinc 0-188%, trace of arsenic, bism uth, alum inium , iron, e tc .; (6) T adanac (Canada), bism uth 4 -5, copper 1 % ; (7) T adanac (Canada), lead 99-987%. The samples had d = (1) 11-36, (2, 3, 6) 11-38, (4) 11-21, (5) 11-35, and (7) 11-37 an d a Brinell hardness of (1) 2-88, (2) 2-71, (3) 3-03, (4) 4-76, (5, 6) 3-20. The tensile strengths in kg./cm .2 were 152, 152, 155, 249, 160, an d 183 and the elongations 40,58, 66, 75-5, 57-5, and 52-5% for sam ples nos. 1-6, respectively. The m elting points of sam ples 1-7 were 328-1, 327-5, 327-6, 30S-9, 327-6, 324-7, and 328-1° C. and th e flash points in sulphuric acid 273, 287, 252, 270, 292, 300, and 270° G —A. R . P. Study of the Absorption of Gases by Metallic Magnesium and Calcium. V. P . Saraev (Zliurnal Tehnicheskoy F iziki (Journal o f Technical Physics), 1932, [B], 2, (5), 442^149).— [In R ussian.] The absorption of th e residual gas in electric bulbs by pow dered m etals has for long been a common in dustrial practice, b u t a detailed stu d y of th e mechanism of gas absorption hns n o t y et been m ade. In th e present work th e absorption of gases by magnesium and calcium, of various degrees of fineness, has been investigated. A bsorption is intensified by ionization, in th e absence of w hich nitrogen and hydrogen are n o t absorbed by magnesium. In th e case of calcium th e ra te of disappearance of the neutral molecules of nitrogen increases w ith increase in th e ra te of pulverization of the m etal. W ith rise in tem perature magnesium gives u p the absorbed gas, b u t w ith calcium th e ra te of absorption is greatly increased. —N . A. The Electrical Resistance and the Critical Point of Mercury. Francis Birch (Phys. Rev., 1932, [ii], 41, 640-648).—The relative resistance of liquid m ercury com pared w ith its value a t 0° C. an d 1 a tm . pressure has been measured between 0° C. and 1200° G , a n d 1 an d 4000 a tm .; values are also given for the instantaneous pressure an d tem p eratu re coeff. of resistance, an d a few m easurem ents were m ade a t higher pressures. All these q u an tities increase w ith rising tem perature, a n d decrease w ith rising pressure. B y assuming th a t below the liquid-vapour critical point the passage through the boiling.

(9) P roperties o f M etals. 3. point will bo accom panied b y a discontinuous change in resistance w hilst above th e critical point th e curve will be continuous, i t is estim ated th a t the critical point is a t 1460 ± 20° C. and 1640 ± 50 kg./cm .2. A bibliography of the literature concerning th e critical constants of m ercury is given.— W . H .-R . The Effect of Strain on Magnetostriction and Magnetization in Nickel. C. W . H eaps (P hys. Rev., 1032, [ii], 42, 10S-118).—Magnetic an d m agneto strictive hysteresis loops have been obtained for pure annealed nickel wire by a heterodyne b eat m ethod.. The m agnetostrictive contraction ~ for both h tensions 6-82 an d 3-70 kg ./m m .2 is given accurately b y th e sam e equation cILjL = — 1-93 x 10~10/ 2 where I is th e in te n sity of m agnetization. F or a tension of 0-72 kg./m m .2, th e equation dL/L = 1-30 x 10_10f 2 holds less accurately. The curves for different tensions cross a t large values of the m agnetic field II, so th a t tension decreases th e m agnetostriction in sm all fields, b u t increases it in large fields. The fa ct th a t th e same equation holds for b o th th e larger tensions is explained b y theories (Becker and K ersten, Z. P hysik, 1930, 64, 665) which suppose th a t tension ten d s to o rien tate the atom ic m agnets across th e axis of tension ; tensions of 3-70 an d 6-82 kg ./m m .2 produce complete transverse orientation, w hilst one of 0-72 kg ./m m .2 leaves th e atom ic m agnets essentially a t random orientation. E xperim ents w ith commercial nickel wire b en t in to a circular arc are also described. This gives one half of the w ire in tension and th e oth er in compression, and a t certain field strengths the m agnetization becomes v ery unstable. I t is shown th a t this explains both th e large discontinuities in the m agnetization curves of F orrer (J. Physique, 1926, 7, 109; 1929, 10, 247) an d th e sm aller B arkhausen effects.—W. H .-R . The Relative Permeability of Iron, Nickel, and Permalloy in High-Frequency Electromagnetic Fields. E dw in Michael G uyer (J . F ranklin In st., 1932, 213, 75-88).— Based on the experim ental m easurem ents described in th e paper, it is concluded th a t there is no anomalous variatio n in th e relative perm eability of iron, nickel, and Perm alloy a t frequencies corresponding w ith th e band of w ave-lengths from 70 to 200 m. The results are co ntrary to those of certain o ther workers.— S. V. W . The Exact M easurement of the Specific Heats of Solid Substances a t High Temperatures. VI.— Metals in Stabilized and Non-Stabilized Condition : Platinum and Silver. F . M. Jaeger, E . R osenbohm , and J . A. B o ttem a (Proc. K . A kad. Wet. Amsterdam, 1932, 35, 763-771).— [In E nglish.] Irreproducible results are obtained for th e sp. h eat of p latin um unless th e m etal is first heated to 1600° C. an d slowly cooled. T his tre a tm en t has th e effect of bringing th e m etal into a stable condition, b u t bears no relation to an y allo tropie change. The tru e sp. h eat of stable platin u m betw een 0° and 1400° C. can be calculated from th e relation cp = 0-031678 + 0-630574 x 10-5t — 0-1624878 x 10-9/2, and th a t of ham m ered p latin u m (0°-1100°C.) from cp = 0-031509 + 0-719102 x lO-^i - 0-94672 x 10-»i2. T he tru e sp. heat (0°-800° C.) of cast silver is given b y cp = 0 055614 + 0-1600766 X l(H i — 0-47223 X 10-si2, and th a t of cold-plated silver by cp = 0-055936 + 0-105607 X lO-'f + 0-18165 X 10-*i2. Comparison w ith values recorded in th e literatu re shows th a t the divergent results are due to working w ith lion-stabilized m etals.— E . S. II. The Exact M easurement of the Specific Heats of Solid Substances a t High Temperatures. VH.— Metals in Stabilized and Non-Stabilized Condition : Copper and Gold. F . M. Jaeger, E . Rosenbohm , an d J . A. B ottem a (Proc. K . A kad. Wet. Amsterdam, 1932, 35, 772-779).— [In E nglish.] Cf. preceding abstract. Stabilized, cast copper lias a tru e sp. h e a t given by cp — 0-092597 + 0-20832 x 10-H, w hilst th e unstabilizcd, cold-rolled m etal has cp — 0-093835 + 0-20684 x 10-*1. A fter heating in a vacuum a t 1050° C..

(10) 4. A bstracts o f P a p e rs. for 5 hrs. an d cooling slowly, th e rolled copper gives a value corresponding w ith th a t of stabilized copper. Gold w hich has been m elted and th en cooled gives cp — 0-03123 + 0-10635 X 10-6f + 0-46558 X lO-8!2, w hilst cold-plated gold gives cp = 0-031341 + 0-93886 X 10~Gi + 0-5127 x 10-8i2. I t is inferred th a t no general prediction can bo made as to th e direction in w hich th e sp. heats of worked and annealed m etals will bo changed.— E . S. H . On the Behaviour of Polonium During the Crystallization of Metals. G. T am m ann an d A. v. Lowis of M enar (Z. anorg. Chan., 1932, 205, 145-162).— E ven m inute q u antities of radioactive elem ents m ay be d etected in m etals by th e aid of the photographic plate. Polonium during th e crystallization of a m etal collects in the polyeutectic, an d w ith it is displaced tow ards th e grain boundaries in which it finally collects. No polonium is ever found along the boundaries of reerystallization grains. From th e w idth of th e blackened areas on the p late it is deduced th a t th e polonium occurs in monomolecular layers. The solid solubility of polonium in silver, tin , bism uth, zinc, cadm ium , copper, antim ony, and tellurium is of th e order of 2-31 — 5-28 X 10-11 % . In con trast to tellurium , polonium forms no intcrm etallic com pounds; it is also practically insoluble in telluridcs. In th e crystallization of m etals containing polonium, separation of this elem ent begins a t tem peratures considerably higher th a n the m elting point of the polyeutectic.— 11. Bl. On the Degassing of Tantalum. N. S. Ivanov (Zhurnal eksperimcnlalnoy i tcoreticheskoy F iziki (Journal o f Experimental and Theoretical Physics), 1932, [A], 2, (3), 162-170).— [In Russian.] H ydrogen on the surface of red-hot tan talu m undergoes dissociation. As th e result of this, th e hydrogen which is given off is adsorbed up to a lim it of 2-4r-3-6 X 1016 atom s/cm .2 on th e surfaces of cold, clean glass vessels. If these are heated to 250° C. th ey no longer adsorb hydrogen.—N. A. On the Change of the Specific H eat of Tin when Becoming Supra-Conductive. W. H . Keesom and J . A. K ok (Proc. K . A kad. Wet. Amsterdam, 1932, 35, 743-748).— [In English.] Between 3-70 and 3-72° K . th e atom ic h e at of tin decreases from 0-0078 to 0-0054. The exact tem perature a t w hich th e change occurs agrees to w ith in 0-01° C. w ith th e tran sitio n to th e superconducting state. T h a t the specific h eat change is connected w ith th e phenom enon of superconductivity is shown by th e fa c t th a t a m agnetic field which im pedes the occurrence of superconductivity also prevents th e change in specific heat. There is no h eat of transform ation connected w ith th e change to th e super conducting state.—E . S. H . Behaviour of Vanadium and V anadium -Iron Alloys towards Hydrogen. L. K irschfeld an d A. Sieverts (Z. Elcklrochcm., 1930, 36, 123-129; C. Abs., 1930, 24, 2093).— A bsorption of hydrogen by vanadium (99%) a t 1 a tm . decreases w ith tem perature from ab o u t 150 c.c. per grm . a t 18° C. sharply to 38-3 c.c. a t 400° C. an d th en more slowly to 2-7 c.c. a t 1000° C. Im purities lower the values. This indicates 946 volumes of hydrogen p er atom of v an a dium , values sim ilar to palladium -hydrogen. The sa tu ra te d m etal is yellow an d darkens in the air. The hydrogen pressure curves by absorption an d evolution are given for various tem p eratu res an d follow m = k \ / P a t 400° C., 600° C., and 800° C. A 9-1% ferro-vanadium goes through a m inim um a t 700° C. and above th a t th e curve is sim ilar to th a t of iron-hydrogen. A 22% ferro-vanadium rem ains much higher, has a m inim um a t 900° C. an d above th a t parallels iron-hydrogen. A 70% ferro-vanadium does n o t sa tu ra te readily b u t parallels the vanadium curve. The curves show- a tw o-com ponent char acte r and the higher th e tem p eratu re th e more closely th e curve approaches a sum of the properties of th e iron an d vanadium present.—-S. G. The Photo-Electric Properties of Alkali Metal Films as a Function of their Thickness. Jam es J . B rady (P hys. Rev., 1932, [ii], 41, 613-626).—T hin films of alkali m etals were deposited upon a silver surface in a high vacuum by.

(11) P roperties o f M etals m eans of a molecular beam under conditions in which th e thickness of the, film could bo estim ated. The effect of th e thickness of th e film upon the photo-electric properties was th en exam ined. W ith cæsium, rubidium , and potassium the general effect is th a t a m axim um threshold w ave-length occurs a t a thickness of a few (1-5 to 3) molecular layers, and a m axim um to ta l photo-electric emission in thicker (5 to 12) molecular layers, w hilst final stable conditions are reached a t a thickness of th e order 12-20 molecular layers, th e exact values varying w ith th e m etal. Sodium behaved q u ite anomalously. T he results are discussed in term s of the Sommerfeld theory, th e adsorbed alkali m etal affecting the p o ten tial wall a t th e surface. I t is concluded th a t th e first few alkali atom s are adsorbed as ions and th e la te r ones as neutral atom s.—W. H .-R . Plasticity and Creep in Metals. H arold Jeffreys (Proc. Itoy. Soc., 1932, [A], 138,283-297).—The equations of plastic flow are derived m ath em atically; a theory of creep and its relation to experim ental results are discussed.—J . T. Mechanism of Plasticity (Preliminary Communication). N. Seljakov (Zhurnal eksperimentalnoy i teoreticheskoy F iziki (Journal o f Experimental and Theoretical Physics), 1932, [A], 2, (2), 140).— [In R ussian.] Cf. this 1932, 50, 597. In plastic deform ation, th e regions adjoining the planes along w hich slip has occurred show a change in th e sym m etry of the crystal lattice which, in the case of cubic lattices, is associated w ith a lowering of the sym m etry of the lattice, duo to elastic slip along the planes in th e direction of the deform ation.—N. A. Cold Deformation, Crystal Recovery, and Recrystallization [of Metals]. H . R eischauer and F . Sauerwald (Melallwirtschaft, 1932, 11, 579-581, 591593, 604-607).— A review, w ith lengthy bibliography, of th e deform ation of m etal crystals, the effect of tem perature and p u rity on th e deform ation process, th e change in physical properties on deforming single and poly-crystals, internal stress, crystal recovery, the form ation of nuclei, a n d grain grow th in recrystal lization, and th e stru ctu re of deform ed and recrystallized m etals.—v. G. On the Dependence of the Endurance Strength on the Crystal Orientation. W . Fahrenhorst, K . M atthaes, and E . Schm idt (Z .V .d .I., 1932, 76, 797).— F atigue tests in th e altern atin g bending m achine of th e D VL have been made on specimens cut in different directions from a sheet of electrolytic copper recrystallized by annealing, so th a t th e crystallites are oriented parallel to one another w ith a cube plane parallel to th e surface of th e sheet and a cube direc tio n parallel to th e direction of rolling. The endurance lim it ( 10Balternations) follows closely the tensile strength, i.e. it is th e same in directions a t 0° an d 90° to th e cube direction, reaches a m axim um a t 45° and a m inim um a t 15° and 75° thereto. E dge deform ation is a minim um a t 45°. The elastic anisotropy of th is ty p e of sheet corresponds com pletely w ith th e anisotropy of single copper crystals. Rolled b u t unannealed sheets show a t least a qualitativ e agreem ent w ith the behaviour of single crystals.— v. G. On the Indefiniteness of the Tensile Limits. Adolf Smekal (Metallwirtschaft, 1932, 11, 551-554, 565-567).—The yield-point of sodium chloride crystals is a sharply defined constant of th e crystal, w hilst th e tensile stren g th has a distribution function the course of which depends on th e sta te of th e m aterial. In applying these results to m etal crystals, th e effect of h eat m ovem ent m ust be taken into consideration.—v. G. On the Change of Hardness of a Plate, Caused by Bending. Sadajirô Ivokubo (Kinzoku no K enkyu, 1932, 9, (10), 447-456).— [In Japanese.] The change of hardness of a plate caused b y bending, was measured b y m eans of the Vickers hardness tester. The m aterials used were Armco iron, 0-2 and 0-7% earbon-steels, copper, brass, alum inium , D uralum in, and magnesium. The hardness-bonding curves show th a t, in cold-rolled specimens, th e hardness on th e convex side of the plate decreases decidedly a t first an d th en som ewhat.

(12) 6. A bstracts o f P a p ers. slowly w ith increasing bending of th e specim en, while on th e concave side it increases only slightly. In annealed specimens th e hardness on th e convex side decreases a t first, an d then, after passing through a m inim um , it increases slightly w ith increased bending of th e specim en; on th e concave side the hardness increases gradually w ith an increased degree of bending. These changes of hardness are satisfactorily explained as th e combined effect of th e applied stress and the w ork-hardening caused by th e bending of th e specimens. — S. G. On the Effect of Torsion on the Density, the Dimensions, and the Electrical Resistance of Metals. Taro U eda (K inzoku no K m b ju ), 1932, 9, (10), 417446).— [In Japanese.] The change of th e density, dimensions, and electrical resistance in Armco iron, Swedish steels, brass, nickel, and copper when tw isted in a torsion m achine were m easured. The densities of iron a n d steel decrease w ith tw isting a n d th eir ra te of decrease is considerable up to th e yield-point. The length of th e specimens increases slightly w ith th e angle of tw ist, b u t beyond th e yield-point th e elongation becomes g reater and greater. The electrical resistance increases as th e angle of tw ist increases, an d up to th e yield-point its rate of increase is very large, th is change being quite sim ilar to th a t of th e shear stress. In th e case of copper an d brass, these changes are in general sim ilar to those for iron an d steel, b u t for brass the rate of change is very large an d for copper v ery small. T hey increase continuously from th e beginning of torsion, and no such a b ru p t change is observed as in iron an d steel. F o r nickel th e change is very large a t th e beginning of torsion, b u t from tliis p o in t it increases only slowly.—S. G. Micrometal Trees. W alther H aas (IFiss. M itt. Osterr. Heilmiltelstelle, 1930, (10), 10-12; Chem. Zenlr., 1931, 102, II , 1109; C. Ai>s., 1932, 26, 4269).—The phenom ena to bo observed w hen salt solutions are electrolyzed bctw’een platinum w ires are described. Photographs of trees of lead, thallium , silver and copper are shown.—S. G. The Diffusion of Metals in the Solid State. G. G rube and A. Jedele (Z. Elektrochem., 1932, 38, 799-807).— Cast cylinders of p u re nickel and of nickel containing m anganese 0-5% were draw n to 5-5 mm. diam . and copper-platcd. A fter various periods of tim e a t 1000°-1025° C. in a hydrogen atm osphere, th in layers were rem oved and analyzed elcctrolytically for copper and nickel. The diffusion coeff., D, is given b y. —F = ^. where C0 — in itial concen. tra tio n (50%), c = resu lt of analysis, t = tim e in days, ; = d ep th of pene tratio n , in cm., and <j>— Gauss’s error integral. The diffusion of nickel into copper in the solid sta te is more rap id th a n th a t of copper in to nickel. In copper-nickel solid solutions, th e diffusion ra te is co n stan t w ith increasing copper content. In the nickel-rich alloys, D = ab o u t 1 x 10-5 cm.2/day, and in the copper-rich alloys ab o u t 4 x 10-5 cm.2/day. W ith manganiferous nickel, th e diffusion ra te of copper is lower, being about 0-3 X 10-5 cm.2/d a y a t the above tem peratures. The diffusion ra te is g reater th e nearer th e tem p era tu re is to the solidification tem perature of th e alloy. The g reatest resistance to corrosion in am m onium carbonate solutions containing hydrogen peroxide occurs w ith the alloy containing 30 atom ic-% nickel. B o th com ponents are attack ed by sulphuric acid solutions containing potassium chlorate. Corrosion cracks increase w ith increasing nickel content up to 75-80 atom ic-% nickel, owing to th e fact th a t th e m agnetic a-phase is less a ttack ed th a n th e non-m agnetic p.— J . H . W . Diffusion. W . R osenhain (Metallurgist (Suppt. to Engineer), 1932, 8, 125-126).—Theories of diffusion are brieflyreviewed. Thesim ple kinetic theory does n o t appear tenable in view of knowledge of th e behaviour of atom s on close-packed lattices, an d th e “ slip theo ry ” is accordingly again p u t forward as a working hypothesis w hich explains th e o u tstanding facts.—R . G..

(13) P roperties o f M etals. 7. On the Heats of Form ation of Nitrides. H I.— The Heats of Solution of Some Metals and Metal Nitrides in Acids. B. N eum ann, C. K roger, and H. K unz (Z. an.org. Chevi., 1932, 207, 133-144).—The h eats of solution of chrom ium, m agnesium , cerium, lanthanum , magnesium n itrid e Mg3N 2, cerium n itride CeN, and lanthanum n itrid e LaN in 1 : 20 hydrochloric acid and of manganese n itrid e Mn5N 2 in 1 : 12-7 sulphuric acid were determ ined.—M. H . A Method of Measuring Very Small Vapour Pressures with the Torsion Balance. K u rt N eum ann an d E rn s t Volker (Z. physikal. Chem., 1932, [A], 161, 33-45).—The vapour pressure of m ercury between 16° an d 70° C. and of potassium betw een 145° and 200° C. has been determ ined.— B. Bl. Tribo-Electricity and Friction. VH.—Quantitative Results for Metals and Other Solid Elements with Silica. P . E . Shaw and E . W . L. L eavcy (Proc. Roy. Soc., 1932, [A], 138, 502-514).—The developm ent of electrification by rubbing pure m etals (pu rity g reater th an 99-7%) including gold, platinum , silver, copper, iron, nickel, alum inium , tin , cadm ium , antim ony, chrom ium , and m etals of comm ercial p u rity , including lead, zinc, bism uth, cobalt, thallium , and selenium against silica, is investigated experim entally and a theory of th e phenom enon is developed. T en factors are involved, an d of these, a group of two, associated w ith th e generation of th e V olta con tact effect, is param ount for m ost elem ents b u t n o t for all.—J . S. G. T. The Theory of Metals.—I. A. H . W ilson (Proc. Roy. Soc., 1932, [A], 138, 594-606).—In teractio n betw een electronic m otions and nuclear vibrations in a m etal is discussed theoretically. The “ m ean free p a th ” of th e electrons is evaluated, and existing theories of conduction are critically exam ined. The refinem ents introduced by Peicrls are considered unnecessary; th eir omission simplifies the theory.—J . S. G. T. The [Electrical] Resistivity of Polycrystalline Wires in Relation to Plastic Deformation, and the Mechanism of Plastic Flow. E . N . da C. A ndrade an d B. Chalmers (Proc. Roy. Soc., 1932, [A], 138, 348-374).—The specific electrical resistance of certain typical m etals, including cadm ium , copper, alum inium , and tin, has been determ ined a t various stages of plastic flow under large stresses, a n d it has been shown th a t th e resistance of m etals which crystallize in the cubic system is unaffected b y th e flotv. The specific resistance of m etals which crystallize w ith a unique axis of sym m etry does n o t change during two of th e three stages into w hich th e flow can be analyzed, viz. during th e initial im m ediate extension and th e final flow a t constant ra te . D uring th e in te r m ediate stage of flow a t dim inishing rate, called th e (3-flow, th e specific resist ance changes by ab o u t 2% in extrem e cases. The results are interpreted on the assum ption th a t the crystallites slip, w ith consequent rotation of th e unique axis, during the (3-flow. On this hypothesis, an increase of specific resistance w ith extension is to be anticipated in th e case of m etals th e crystals of w hich have slip planes parallel to th e unique axis. In th e case of crystallites having slip planes norm al to th e unique axis, there should occur a decrease of specific resistance on extension, in thoso cases where th e resistance is g reatest along the unique axis. The theory is supported by results obtained a t low tem p era tures w hen m arked im m ediate stretch occurs b u t no (3-stretch. I n these circum stances a n increase of resistance is obtained w ith cadm ium while a decrease occurs a t ordinary tem peratures. T his increase is a ttrib u tab le to extensive tw inning.—J . S. G. T. On the Electrical Properties of the Group of So-Called “ Semi-Conductors.” A. Schulze (Helios (Fachzeit.), 1932, 38, 201-204, 211-213).—The electrical behaviour of th e sem i-conductors, silicon, graphite, titan iu m , zirconium, hafnium , thorium , germ anium , boron, arsenic, and tellurium are discussed w ith reference to the literatu re. I t is pointed o u t th a t, so fa r as investiga tions have been m ade, single crystals of these substances have a metallic.

(14) 8. A bstracts o f P a p e rs. conductivity, so th a t th e negative tem perature coeff. of polycrystalline m aterial is to be a ttrib u te d to a grain boundary effect.— v. G. Barkhausen Effect. III.— Nature of Change of Magnetization in Elementary Domains. R ichard M. Bozorth and Jo y F . Dillinger (Phys. Rev., 1032, [ii], 41, 345-355).— The small sudden changes in m agnetic m om ent w hich occur when a m etal is m agnetized have com ponents b o th parallel and perpendicular to the direction of the m agnetic field. The la tte r effect is detected for th e first tim e w ith annealed and hard-worked iron, and annealed Perm invar containing iron 30, cobalt 25, nickel 45% , w ith 0 T % silicon as im purity. The relative im portance of th e two effects depends on the m aterial, and on the degree of m agnetization of th e specimen as a whole. T he new transverse effect is relatively sm all when th e magnetizing field 11 is less th a n th e coercive force, and m ay bo equal to or greater than the longitudinal effect when th e m agnetization of th e m aterial approaches saturation. The d a ta are in terp reted in term s of the dom ain theory, and suggest th a t m agnetic m aterials are divided into sm all dom ains, each of which is m agnetized to satu ratio n , th e m agnetization being controlled in some dom ains by strain, and in others by th e crystal lattice, the relative effect of strain being increased by cold-work. Perm invar shows peculiarities, and m ay be a m ixture of tw o magnetic m aterials.—W . H .-R . On Ferromagnetism and Related Problems of the Theory of Electrons. P au l S. E pstein (Phys. Rev., 1932, [ii], 41, 91-109).—Theoretical. S tartin g w ith th e theory of Slater (this J ., 1930, 44, 46S) concerning cohesion in m etals, the electronic theory of hom opolar bonds in metallic crystals is developed for both m agnetic and non-m agnetic elem ents. As suggested b y Heisenberg, the P au li exclusion principle influences th e orientation of th e spins of th e valency elec trons, and th e deciding factor is th e sign of th e H eitler-L ondon interchange integral J v M aterials w ith large negative values of J , are non-m agnetic, those w ith sm all values (either + or —) of J 1 are param agnetic, an d those w ith large positive values m ay be ferrom agnetic. The theorv of Bloch (Z . Physik, 1928, 52, 555; 1930, 59, 208; 61, 206; 1932, 74, 295)% confirmed for n o n m agnetic m etals, b u t E .’s results for m agnetic m etals are different and new. The new' theory dem ands th e existence of a block stru ctu re in ferrom agnetic m etals, the blocks being in a sta te of perm anent spontaneous m agnetization, th e polarity of which changes frequently, its direction being related to th e crystallographic axes, although th is relation is ignored in th e calculations. A t low tem peratures th e sp. h eat of a m agnetic m etal is given by c = 0-20SsR(T ¡8)21'2, w here R is th e gas constant, s th e num ber of valency electrons per atom , and 8 is closely related to th e Curie point.— W . H .-R . The Ferromagnetic Moments of the Elements and the Periodic System. Charles Sadron (A nn. Physique, 1932, [x], 17, 371-452).—The m agnetic p ro perties of binary alloys of nickel an d of cobalt have been exam ined as a function of th e percentage com position; only those alloys in which simple solid solu tions are form ed have been studied. The behaviour of m anganese-nickel and m anganese-cobalt alloys suggests th a t th e atom s of manganese are oriented in a direction parallel to th a t of th e surrounding ferrom agnetic atom s, and on th e basis of this hypothesis a m om ent of 15-0 m agnetons is attrib u te d to th e manganese atom . B y extension of th e hypothesis th e atom ic m om ents of 15 o th er m etals have been determ ined. F o r th e elements in an y one column of th e periodic table the atom ic m om ent is constant. F o r th e m etals from copper to vanadium in th e first long period, th e atom ic m om ent increases w ith increasing atom ic num ber according to a linear law, th e increm ent being 5-25 magnetons, w hilst for those from vanadium to nickel th e rate of change is linear b u t negative, and am ounts to — 4-0 m agnetons.—H . F . G. Experiments on the Nature of Ferromagnetism. Francis B itte r (Phys. Rev., 1932, [ii], 41, 507-515).—The presence of irregularities in ferrom agnetic crystals has been detected by allowing a fine suspension of ferric oxide particles.

(15) P roperties o f A llo ys. 9. in ethyl acetate to settle on th e surface of carefully prepared crystals. E x p e ri m ents were m ade both w ith and w ith o u t an applied field on crystals of iron, cobalt, nickel, and of alloys of iron w ith silicon or nickel. On crystals of cobalt straig h t lines are obtained on some crystals, w hilst others give sp o tty patterns in which the spots ten d [to form a hexagonal array. The general tendency is to form line p attern s in which th e lines can appear in 3 directions in each crystal of iron, 4 in nickel, b u t only 1 in cobalt. I t is suggested th a t the patterns are somehow related to th e three (100) axes in iron, th e four (111) axes in nickel, and the single (0001) axis in cobalt, and it is significant th a t in each case the axis m entioned is th e direction of easiest m agnetization. The p attern s are readily destroyed by surface strains.—W . H .-R . I I .— P R O P E R T IE S O F ALLOYS. Preparation oî Single Crystals oî Duralum in, Tin-Bronze and “ A lum inium Bronze ” and the Study of their Properties. M. P. Slavinsky an d A. P. Belaiev (Metallurg (The Metallurgist), 1931, 7, (1), 3-19).— [In R ussian.] Form er work on th e production a n d properties of single crystals of alum inium an d its alloys is sum marized. Owing to th e inconclusive n atu re of existing d a ta and the possibility of practical value resulting from changes in p ro perties (e.g. electrical conductivity), single crystals of pure alum inium and D uralum in were prepared an d investigated. The specimens were obtained both by very slow cooling of castings and also by repeated work-hardening an d normalizing. W ith D uralum in th e first m ethod gave a stru ctu re showing large inclusions of CuA12, only a v ery small proportion of the copper rem ain ing in th e solid solution. The mechanical properties were poor and showed nothing of note. The second m ethod did n o t give a single cry stal and had no m arked influence on th e properties. Slow cooling of tin-bronze (with or w ithout additions of zinc an d phosphorus) and “ alum inium -bronze ” p ro duced a dendritic structure, which, nevertheless, was monocrystallinc in type, except when liquation phenom ena could tak e place. Specimens of these alloys obtained by rapid cooling a n d consisting of several crystal grains were converted into a condition approxim ating to single crystals by annealing, w ith a resulting decrease in mechanical properties as is sometimes observed on annealing castings which have been made tinder certain conditions of cooling. Finally, the process of recrystallization by w ork-hardening an d annealing gives these alloys a single crystal stru ctu re which is, however, n o t identical w ith th a t obtained by very slow cooling from th e m olten condition.—M. Z. Strength Tests on Thin-W alled Duralum in Cylinders in Torsion. Eugene E . L undquist (U .S. N at. Ailvis. Cttee. Aeronautics, Tech. Note No. 427, 1932, 1-8, and appended plates an d diagram s).—Torsion tests on D uralum in cylinders of specified dim ensions arc described. The influence of th e ratios length/radius and radius/thickness on th e ty p e of failure is discussed, and an equation for calculating th e shearing stress a t failure is given, in the form : S , = K ,E I ( j ) ’1, where n is a constant for an y given m aterial, K , varies w ith the length/radius ratio p E is th e m odulus of elasticity, r th e radius, and t th e thickness of the cylinder. In th is case, th e ten ta tiv e value of 1-35 is assumed for », and corresponding values of K , and r are given. The form ation, direction, and num ber of shearing wrinkles and th e influence of slight im perfections are discussed.—P . M. 0 . R. Hardening of Non-Ferrous Alloys. V. Christiansen (T eknisk T ids., U ppl. C, Bergsvetmskap. 61, 1931, 39-43, 47-53; C. Abs., 1932, 26, 5285).—The principles an d courses of th e hardening processes for non-ferrous alloys on.

(16) 10. A bstracts o f P a p e rs. annealing arc described. The theory of th e “ critical d ispersion” of CuAL crystals in D uralum in during its after-hardening a t room tem p eratu re is discussed and criticized. Such a separation of crystals could n o t be detected microscopically or by X -ray m ethods, n either could changes in th e solid solution param eter bo observed nor indications of new interferences originat ing from now kinds of crystals. A scries of now observations also offers difficulties in applying th e simple explanation of the dispersion theory. In a solid solution of tw o metals, as, for example, of copper an d alum inium in D uralum in, the electrical resistance should decrease if a separation in one form or another takes place, because th e m ain con stitu ent is thereby rendered purer. D uring th e process of hardening D uralum in a t room tem perature the electrical resistance generally increases. I t is difficult to explain th e fact th a t when D uralum in and oth er alloys are first p erm itted to harden a t room tem perature for a certain tim e a fter quenching a n d la te r a t higher tem peratures, a decrease in hardness will first take place, a fter w hich th e h a rd ness increases faster and to a higher degree th a n before. The mechanical properties of alloys of th e D uralum in typo an d th e changes in these resulting from different hardening processes are described. The effects of th e presence of magnesium, lithium , manganese, and silicon in such alloys are discussed. A series of alloys w ith copper as th e m ain constituent, such as copper-beryllium alloys and Corson and H eusler alloys; th e ir hardening processes; mechanical, electrical, and chemical properties, are described. A num ber of “ noble ” m etal alloys capable of being hardened are also discussed.— S. G. Contribution to the Study of A lum inium -Iron-C hrom ium Alloys.—n . Ch. Taillander {Rev. MU., 1932. 29, 34S-356).—Cf. th is ./., 1932, 50, 600. M etallographic investigations and mechanical tests are described. T he la tte r include tensile tests, notched-bar tests, an d hardness te s ts a t norm al and a t elevated tem peratures. T he alloys contained u p to 2-29% of chrom ium and 4-18% of iron. Therm al analysis an d m icrographic analysis indicate a tern ary eutectic a t 2% of chrom ium an d 1% of iron. D ilatatio n te s ts indi cate dim inution by iron and chrom ium . 2 to 2-5% of iron a n d chrom ium m ay be introduced into alum inium w ithout rendering i t v ery brittle. The m axim um tensile stress and notched-bar values are im proved. In this range of composition the alloys retain th e w hite colour of alum inium .— H . S. Binary Aluminium-M anganese Alloys. M. B osshard {Light Metals Research, 1932, 2, (11), 9-10).—The tensile strength, elongation, an d electrical conductivity of alum inium -m anganese alloys containing 0 ’5-3-5% of m an ganese have been determ ined. Values are ta b u la te d for sheet 1 m m . and 2 mm. thick. The sheet was reduced 80-90% b y cold-rolling a fte r a n in te r m ediate anneal a t 420° C. The tensile stren g th was increased by th e addition of m anganese up to 1-4%, after which fu rth er additions h ad little effect. The conductivity was reduced b y manganese, th e effect being less pronounced after the addition of 1-4% manganese. The behaviour of th e alloys during hot- and cold-rolling w as sim ilar to th a t of alum inium . The corrosion rcsistance of those w ith more th a n 1% m anganese w as found to be superior to th a t of 99-5% alum inium when tested b y both M ylius’s tests.— J . C. C. Aluminium-Silicon Alloys.—I. ------ Bronicwski an d ------ Smialowski (Rev. MU., 1932,29,542-552).—The m ethods of investigation em ployed include therm al analysis, electrical resistivity, therm oelectric force, solution potential, dilatation, hardness tests, an d m icrography. T he alum inium used was of 99-7% purity, and th e silicon 97-3%, th e la tte r containing 1-2% of iron and T 5% of alum inium as im purities. B. an d S. conclude from th e ir results th a t th e Al-Si eutectic occurs a t 11-5 atom ic % silicon a n d m elts a t 575° C. The silicon-rich solid solution contains 96% of silicon a t th e solidus tem perature an d 97% a t room tem perature. The alloys containing ab o u t 94% of silicon have a specific resistance of 0'07 ohm s/em .3 an d a tem p eratu re cocff. of about.

(17) P roperties o f A llo ys. 11. zero. A therm oelectric couple composed of alloys of 9G an d 97% of silicon gives a therm oelectric force E 10° = 6 5 6 1 + 0-98t2, th e couple being one of the m ost powerful know n up to th e present. The hyper-eutectic alloys m ay be used as light antifriction alloys provided th a t th e steel journals have a Brinell hardness above 500° C., e.g. are nitrogen-hardened. In a general w ay the indirect m ethods of investigation em ployed in establishing th e stru ctu re of alum inium -silicon alloys gave norm al results in spite of the ra th e r peculiar properties of silicon.—H . S. Characteristics of Cast Aluminium Alloys as Influenced by their Composi tion and Structure. C. Panseri (A llum inio, 1932,1,279-307).—T he technique of casting pistons for internal com bustion engines is described, and the maerostructurc and compositions are correlated w ith th e casting properties. The problem of stresses derived from therm al treatm en t, an d th e effects of various treatm en ts on certain alloys have been studied. The equilibrium diagram s of the silicon-m agnesium -alum inium an d nickel-copper-m agnesium silicidealum inium system s havo been fully investigated. A description is given of a new alloy—D uralite—containing copper 3, silicon 0-7, nickel 0-5, magnesium 0-5, iron 1-5, titan iu m 0'2% . I t is ono of aseries of alloys wliich a tte m p ts to combine the good technical properties of “ Y ” alloy w ith th e good casting properties of alloys containing largo q u antities of copper. C ertain other properties of various piston alloys arc discussed, and it is concluded th a t the best alloys are those of th e D uralite type.—G. G. Special [Proprietory] Aluminium Alloys. E dm und R ichard Thews (Metallborse, 1932, 22, 545-546, 577-578).—An alphabetical list of proprietory' alloys w ith notes of th e ir composition where published.— A. R . P. On the Magnetostriction of Iron-Cobalt Alloys. Yosio M asiyam a (Sci. Rep. T óhohi Im p . Univ., 1932, [ij, 21, 394-410).— [In English.] The whole series of alloy's has been studied. The longitudinal an d transverse effects are in opposite senses an d th e change of volume is a differential effect. A m arked discontinuity was observed in th e expansion-concentration curve in both th e longitudinal an d transverse effects a t ab o u t 80% of cobalt. This corresponds w ith the phase change from a- to y-solid solution.—E . S. H . On the Grain-Refinement of Copper-Rich Alloys by Peritectic Reaction. Ju -n Asato (K inzokn no K enkyu, 1932, 9, (9), 392-416).— [In Japanese.] I t is well know n th a t th e crystal grains of “ alum inium -bronze ” become very line when iron is added, b u t there has been no clear explanation for this. A. has found th a t this grain-refinem ent is closely related to the peritectic reaction between copper and iron, from experim ents w ith copper-iron, copperzinc-iron, copper-tin-iron, copper-m anganese-iron, and copper-alum inium iron alloy's. A. has also found th a t in th e above series of alloys iron m ay be replaced by cobalt as th e la tte r is sim ilar to iron in its behaviour tow ards copper.—S. G. The Reaction Capacity of Alloys and its Dependence on Melting or on Transformations in the Solid State. I.— Chemical Reactions of Copper-Tin Alloys with Lime or Quartz in Oxygen. J . A rvid H edvall and F . Iian d er (Z. anorg. Chem., 1932, 203, 373-389).— Interm etallic com pounds react w ith alkaline-carth oxides in th e presence of oxygen on heating, especially a t tra n s form ation tem peratures or a t tem peratures a t which break-up of th e lattice occurs. The reactions between CuSn and lime and between CuSn or Cu3Sn an d S i0 2 have been investigated. T hey are of im portance in respect of th eir effect on th e stab ility of m elting crucibles.— B. Bl. Analyses of Old Bronzes. J . Sebclien (Avh. Norske Vid.-Alcad. Oslo, 1931, (3), 3 -9 ; C. Abs., 1932, 26, 4575).—Cf. this J ., 1932, 50, 349. A bronze nail from the gates of th e palace of Shalm anesir I I contained copper 81-1, tin 11-4, lead 0-47, iron 0-51, zinc 0-19, and arsenic 0-12%. Old Chinese bronzes generally' contain a high proportion of lead w ith little or no zinc..

(18) 12. A bstracts o f P a p ers. K nife coins of th e Ming scries contained copper 47, tin 1-5, zinc 1, lead 43-5, and arsenic 1% . Analyses of m any old Norwegian bronzes gave tin 3-17% , and no evidence was found of a Copper Age preceding th e Bronze Age. The compositions of 10 bronze coins of various countries m inted betw een 90 B .C . an d A . n . 1828 are tab u lated .—S. G. Properties and TJses o£ Lead-Rich Bearing Bronzes. Anon. (Metallbörse, 1932, 22, 483).—The composition an d mechanical properties of some leaded bearing bronzes for special purposes are tab u lated . The inform ation given is taken chiefly from th e work of Clamer (./. Franklin Jnst., 1903,156, 49) and from publications of th e A.S.T.M. (see Met. In d . (N . Y .), 1931, 29, 517). —A. R . P . The Equilibrium Diagram of Lead-Tin Bronzes. Jöszef Vcszelka (Bdnydszati is Kohdszati L a y ok, 1932, 65, 212-220, 237-24-1; Chem. Zentr., 1932, 103, II, 1504).—The mechanism of crystallization of co p p er-tin alloys w ith constant lead content of 2 an d 5% is described. Sim ilar effects have been observed to those found by B auer and H ansen in th e copper-zinc-lead system. Sectional diagram s for th e 2 and 5% lead alloys have been constructed based on mierographic exam ination. G iolitti and M arantonio’s observations (Gazz. chim. ital., 1910, 40, 51) on th e d istrib u tio n of lead in the constituents of cast bronze are shown to be erroneous.— A. R . P . The Technological Properties of Nickel-Bronzes. Anon. (Metallbörse, 1932, 22, 1134-1135).—A review of recent w ork on the effect of additions of 1-3% of nickel on the mechanical properties of bronze w ith u p to 12% tin or tin -f- zinc.—A. R . P. The Separation of the a-Phase in ß-Brass. M. Straum anis and J . W eerts (Z. Physik, 1932, 78, 1-16).—The process of separation of th e cubic facecentred u-phaso from th e copper-rich cubic space-centred ß-phaso of th e copper-zinc alloys has been investigated by X -ray and microscopic exam ina tion of single-crystals of th e alloys. T he a-crystallitcs are found to be p re ferentially oriented in 24 different s tra ta independently of th e n atu re of the heat-treatm ent. The accom panying lattice transform ation can be interpreted in term s of slip processes an d is crystallographically reversible. The m echan ism involved in th e orientation and transform ation appears to be the reverse of th a t suggested by K urdjum ow and Sachs for th e austen ite-m arten sitc transform ation. U nder conditions of considerable super-cooling and m arked supersaturation, th e character and arrangem ent of th e <x-crystallites are con trolled by th e slip mechanism in accordance w ith th e sym m etry of th e ß-lattice, w ith the resulting production of considerable regions of lam inar precipitation. Rod-like precipitation characterizes higher annealing tem peratures.—J . T. The a - and ß-Solid Solutions of the Copper-Zinc Alioys and the Corresponding Liquid Solutions in Equilibrium with Them Examined Thermodynamically. F . H . Jeffery' (Trans. Faraday Soc., 1932, 28, 452-455).—Therm odynam ic analysis of th e equilibria in the copper-zinc sy’stem s indicates th a t th e liquid solutions in equilibrium w ith th e x- and ß-solid solutions consist of CuZn4 dissolved in monatom ic molecules of copper, th a t th e a-solid solution consists of CuZn, dissolved in m onatom ic copper, and th a t th e ß-solid solution consists of CuZn, dissolved in monatom ic copper. The complex n atu re of these liquid and solid solutions seems to be consistent w ith th e form ation of m etastable states. As the corresponding cop p er-tin solid solutions consist of Cu.,Sn and tin in copper, respectively', th e analogy found between th e a- an d ß-phases in the copper-tin and copper-zinc system s by X -rays is n o t in accordance w ith th e laws of therm odynam ics, assuming J . ’s premises to be correct.— A. R . P. On Transformation Processes in ß-Brass and ß-Silver-Zinc Alloys. J. W eerts (Z. Metallkunde, 1932, 24, 265-270; discussion, 270).—The separation of cubic face-centred a from cubic body-centred ß in brass an d th e tra n s form ation of cubic body-centred ß into hexagonal t in silver-zinc alloys have.

(19) P ro p er lies o f A llo ys. 13. been studied by rdntgenographic and micrograpiiic exam ination an d by m easurem ents of th e electrical resistance and hardness during agoing of quenched specimens. B oth transform ations are governed by stric t erystallographic lattice relations, th e form er being characterized by a gliding of the atom s sim ilar to th a t of th e m artensitc transform ation, and th e la tte r, by grow th from a constant num ber of nuclei w ith a constant linear velocity of crystal grow th.—M. H. Alloys of Gallium. W. K roll (Mctallwirtschaft, 1932,11,435-437).— Alloys of gallium w ith iron, nickel, copper, zinc, magnesium, bism uth, alum inium , lead, cadm ium , and tin have been investigated. Those w ith th e first three m etals do not age-liarden. Alloying copper w ith gallium produces only a very sm all hardening effect. More th a n 0-5% gallium in zinc spoilR the mechanical properties, especially a t high tem peratures. Magnesium dissolves a m aximum of about 4 -6 % gallium , b u t th e alloys can be age-hardened only slightly. Low-m elting-point binary and polynary alloys of gallium w ith cadm ium , bism uth, lead, tin , and zinc contain eutectics; the alloy of gallium w ith 12% tin m elts a t 15° C. The eutectic arrest p o in t can be d etected in alloys w ith very high percentages of th e second and th ird m etals. Lead w ith 0-2% gallium is as b rittle as 12% antim onial lead. B inary alum inium alloys w ith sm all percentages of gallium cannot be age-hardened, b u t can be readily rolled, addition of gallium increasing th e hardness of alum inium only slightly. T ernary gallium -m agnesium -alum inium alloys agc-harden in a sim ilar way to zinc-m agnesium -alum inium alloys, a sm all effect being observed a t room tem perature and a m axim um hardness of 112 being obtained on ageing above 100° 0. L ithium -gallium -alum inium alloys behave sim ilarly. The 4% gallium -alum inium alloy slowly disintegrates in m oist air.—v. G. Coloured Gold Alloys. E . Vincke [M itt. Forschungsinst. Edelmetalle, 1932, 6, 1- 8).—Form ula:, m elting points, and colour of so-called red, yellow, and w hite gold alloys of various carats are tab u lated and th e m elting and working conditions are discussed.—A. R. P. The Super-Conductivity of Gold-Bismuth [Alloys]. W . J . de H aas and T. Ju rriaan se [Proc. K . A hid. IVet. Amsterdam, 1932, 35, 748-750).— [In English.] Cf. th is J ., 1932, 50, 16. X -ray analysis has shown th a t goldbism uth alloys containing 10, 20, or 40% of bism uth contain a phase of the composition Au2Bi, which can be separated by washing o u t the bism uth w ith n itric acid. The com pound A u,Bi becomes superconducting in liquid helium a t th e sam e tem perature as th e gold-bism uth alloys, and is therefore held to account for the superconductivity of th is series of alloys. The crystals of AiioBi are cubic, having an edge of 7-94 A. The den sity determ ined by X -ray analysis is 15-70, agreeing w ith th e pyknom etric value 15-46.—E . S. H . On the Law of Additive Atomic Heats in Interm etallic Compounds. IX.— Compounds of Tin and Gold, and of Gold and Antimony. J . A. B ottem a and F. M. Jaeger [Proc. K . Akcul. Wet. Amsterdam, 1932, 35, 916-928).— [In English.] The existence of pure, hexagonal AuSn has been confirmed by X -ray exam ination an d chemical analysis. I ts stru ctu re is analogous to th a t of P tS n . The sp. volume is ab o u t 12% sm aller th a n the sum of the sp. volumes of its com ponents. The tru e sp. heat of AuSn can be calcrdated a t any tem perature I from th e relation cp = 0-039649 — 0-3358 x 10~6 1 + 2-9337 X 10 s The molecular h eat of th e com pound is shown to be less th a n th e sum of th e atom ic heats of th e com ponents (as w ith PtS n). The sp. heat of Sn in AuSn is, however, different from th a t of Sn in P tS n. The compound AuSb2 was produced by m elting th e constituents together in hydrogen and tem pering and re-m elting th e mass u n til a homogeneous product was obtained. I t possesses a pyritc structure. A t 355° C. th e y form is transform ed into a ¡3 form , which is converted into an a form a t a b o u t 405° C. The tru e sp. heats of these modifications arc given by yce = 0-043626 —.

(20) 14. A bstracts o f P a p e rs. 0-189064 X 1 0 -* /+ 0-70563 x 1 0 - t~, (3cp = - 0-169785 + 0-22014 x 10' 2 1 - 0-42252 x 10-5 i2, acp = 0-45389 - 0-39127 x 10' - 1 + 0-70257 X 10-5 11. T he sp. h eat of antim ony has also been determ ined. T here is a tra n s form ation point a ^±¡3 a t a b o u t 413° C. The results arc expressed by the formulae |lcp = 0-0535656 - 0-46635 X 10~4i + 0-15497 X 10-° 1-, olc„ = 0-534496 — 0-4522 x 10—t -f- 0-7944 X 10“5 t2. The rule of additive atom ic heats is again n o t valid, b u t th e deviation is in th e opposite direction; the molecular h eat of A uSb. is g reater th a n th e sum of the atom ic heats of the constituents.—E . S. H . On the Law of Additive Atomic Heats in the Case of Interm etallic Mixed Crystals. X.—Silver and Gold. J . A. B ottcm a an d F . M. Jaeg er (Proc. K . Akad. Wet. Amsterdam, 1932, 35, 929-931).— [In English.] An alloy con taining gold 25-56 and silver 74-44 atom s % has a tru e specific h eat given by Cj, = 0-04561 + 0-1118 x 10-4/. Comparison w ith th e values for pure gold a n d silver shows th a t there are sm all deviations from th e rule of additive atom ic heats even in m ixed crystals and th a t th e deviations increase with rising tem perature. The deviations are n o t considerable, except above 600° C. —E . S. H . The Lead-Rich Alloys of the System Lead-A ntim ony Examined Therm o dynamically. F . H . Jeffery (Trans. Faraday Soc., 1932, 28, 567-569).—T he equilibria a t the lead end of th e lead-antim ony system can be explained therm odynam ically only on th e assum ption th a t th e com pound P b 2Sb exists in th e liquid and solid solutions dissolved in monatom ie molecules of lead. The form ation of th is compound in solid solution accounts for th e hardening effect of sm all q u an tities of antim ony on lead. I t is pointed ou t th a t X -ray analysis fails to d etec t th e presence of a com pound in th e lead-an tim o n y alloys.— A. 14. P . Manganese-Nickel Alloys.—I.-H . A. D ourdine (Rev. Met., 1932, 29, 50 7 518, 565-573).— (I) T herm al analysis indicated solid solution on th e nickel side up to 38% of m anganese, and on the m anganese side up to a b o u t 59% . A t interm ediate concentrations (38-59% manganese) a new con stitu en t is form ed in the last stages of crystallization. A t concentrations betw een 32 and 68% of manganese, a scries of therm al effects in th e solid sta te is observed, and special atten tio n has been paid to these by D. (II) The m angancscnickcl alloys crystallk-.c p a rtly in a stable condition an d p a rtly in an unstable condition on cooling a t th e usual rates. The unstable condition occurs between 43-2% and 58-5% m anganese. I n th e unstable condition th e alloys form an unbroken series of solid solutions except, perhaps, a t concentrations in th e vicinity of pure manganese. The change to th e stable condition occurs com pletely when th e alloys are m aintained for a more or less prolonged tim e in the vicinity of th e solidus. In th e stable condition, th e range of solid solutions is broken b y tw o heterogeneous regions between 43-2 an d 48-37% and 49 an d 58-5% of manganese respectively. In these heterogeneous regions three phases are distin g u ish ed : (3 solid solution of m anganese in n ick el; y solid solution of nickel in y-manganese, a n d the 8-phasc. The compound MnNi is responsible for th e 8-phase, a n d th e compounds M n3N i2 an d Mn3Ni4 (s phase) probably occur. Cobalt a n d iron additions reduce considerably the degree of instability of th e unstable system . Silicon accelerates th e y > 8 transform ation, w inch in these alloys proceeds slowly an d only in a narrow interval of tem perature.—H . S. K anthal. J . H . Russell (Metallurgia, 1932, 6, 195-196).—A new electrical resistance m aterial in which alum inium , chrom ium , and nickel are alloyed, and w hich is produced in 3 grades in w hich th e perm issible tem peratures of heating elem ents m ade from them are 1325°, 1250°, an d 1050° C., respectively. These alloys have a higher sp. resistance, and a lower sp. gr., th a n niekel-chrom ium alloys, an d in the presence of sulphur are a ttack ed only to a very sm all degree..

(21) P roperties o f A llo ys. 15. K an th al alloys have also high oxidation-resisting qualities, and are produced in strips, castings, and wires. E lem ents m ade from these alloys have been used successfully in furnaces for hardening high-speed steel, glass-melting, heattreatin g of stainless steel, case-hardening, enamelling, and sintering tungsten carbide.— J. W . D. Investigation of the Magnetostriction and Magnetization of Single Crystals of the Iron-Nickel Series. F ritz L ichtenbergcr (A nn. Physik, 1932, [v], 15, 45-71).—Single crystals of iron-nickel alloys w ith 30-100% nickel have been prepared in a vacuum furnace b y B ridgm an’s m ethod and th eir m agneto striction and m agnetization m easured. The direction in which th e alloys are m ost readily m agnetized is (100) for 30-70% nickel and (111) for 71-100% nickel.—v. G. On the Equilibrium Diagram of the Nickel-Zinc System. K anzi T am aru (Sei. Pep. Tôhoku Im p. Univ., 1032, [i], 21, 344-303).— [In English.] The equilibrium diagram of th e nickol-zinc system has been constructed from therm al analyses a n d dilatom etric an d electrical resistance measurem ents. The effect of zinc on th e m agnetic transform ation of nickel has also been studied. The a solid solution extends to 01-61% nickel a t 1403° C. The ß solid solution on th e zinc-rich side reaches 37-5% nickel a t th e outcctic tem perature. The eutectoid transform ation of th e ß solid solution occurs in alloys containing 45-1-24-4% nickel a t a m ean tem perature of 675° C. The com pound NiZn form s a 8 solid solution which is homogeneous between 49 and 45-1% nickel. The reaction a - f ß — >■8 occurs a t 804° C. T hecom pound N iZn, has a solubility of 1-4% nickel on the nickel side. The liquidus and eutectic horizontal near N iZ n„ found by differential therm al analysis, invali d ate the view of B auer an d H ansen regarding th e peritectic reaction. X -ray analysis shows th a t th e stru ctu re of the a solid solution is face-centred cubic, th a t of ß an d 8 hexagonal, an d th a t of y cubic.—E. S. 11. Magnetic Susceptibility and Electrical Resistance of the Palladium -Silver and Palladium-Copper Solid Solutions. Börje Svensson (A nn. Physik, 1932, [v], 14, 699-711).— In th e binary- solid solution system silver-palladium the susceptibility falls from th a t of puro param agnetic palladium to zero a t 50 atom ic-% silver and approxim ates to th a t of pure diam agnetic silver a t 60 atom ic-% silver. C opper-palladium solid solutions behave similarly. F or the oriented com pounds CuPd and Cu3P d th e diam agnetic susceptibility is 5 0100% greater th a n th a t for th e unoriented solid solutions of th e same composition.—v. G. Electrical Properties of Dilute Solid Solution Alloys. II.— Resistance of Silver Alloys. J . O. Linde (A nn. P hysik, 1932, [v], 14, 353-306).— Cf. this J ., 1932, 50, 15. The electrical conductivities of silver alloys w ith elements of atom ic num ber 29-33, 46-51, an d 78-83 have been determ ined. Solid solutions in silver of m etals which do n o t belong to th e transitional group follow X orbury’s rule, w hich can be more precisely state d as follows : th e atom ic rise in resistance is proportional to th e square of th e distance (difference between th e group num bers) of th e elem ent in th e periodic system from th e silver group.— v. G. Mechanical Properties of W hite Bearing Metals a t Various Temperatures. Anon. (Metallbörse, 1932, 22, 1006-1007).—T ests on th e resistance to wear of various types of bearing m etal a t 20-200° C. have been m ade in heavy m otor lorries ; th e results show th e g reat superiority of th e tin -ric h alloy-s. Cadm ium -zinc an d barium -calcium alloys are superior to th e usual lead-rich alloys.—A. 11. P . High-Percentage Tungsten Carbide Alloys and their Technical Application. Sven G. Lind (Teknisk 'l'ids., U ppl. C., Bergsvetenskap. 62, 1932, 9 -1 4 ; G Abs., 1932, 26, 5532).—The m anufacture of alloy-s of cem ented tungsten carbide and cobalt an d th e ir m echanical properties are described. The.