METALLURGICAL A B ST R A C T S
(G E N E R A L A N D N O N -F E R R O U S )
Yolume 3 MARCH 1936 Part 3
I.— P R O P E R T IE S O F M ETALS
(Continucd Irom pp. 29-35.)
Study of th e M anufacture, Properties, an d Uses of Refined A lum inium . R . G adeau (JRev. M U ., 1935, 32, (11), 503-508).— T he B e tts , H oopes, a n d A .F.C.
processes, em ployed b y th o C om pagnie d ’A lais, F ro g es e t C am argue, are described. T he A .F.C. process yields alu m in iu m o f 99'99% p u rity . G. com- pares th e m ore im p o rta n t p h y sical p ro p ertie s w ith those o fless p u re alum inium . Tho h ig h -p u rity m a te ria ł possesses m uch inereased resistan ce to corrosion an d g re a te r d u c tility .— H . S.
* 0 n th e F iguring an d Correcting of M irrors by Controlled Deposition of A lum inium . J o h n S tro n g a n d E . G aviola (P h y s. E ev., 1936, [ii], 49, (2), 207).
—A b stra c t o f a p a p e r re a d before th e A m erican P h y sic a l Society. B y co n tro lled d eposition o f m etals ev a p o ra te d in a y a cu u m , i t is possiblo to change th e figurę o f reflecting surfaces q u a n tita tiv e ly . A spherical 12-in. m irro r has been parab o lized rep eated ly , a surface being o b ta in e d p e rfe c t w ith in .-}g o f a w ave-length. A 5g-in. sp h erical m irro r lias been parab o lized w ith th o optical axis o u tsid e o f its p erip h ery . A defective p arab o lic m irro r w as corrected o f tu rn e d u p a n d dow n edges a n d asy m m etric zones. A convex spherical C assegrain m irro r w as hyperbolized.— S. G.
♦Photoelectric W ork-F unction of B arium . R . J . C ashm an a n d N . C.
Ja m iso n (P hys. Iłev., 1936, [ii], 49, (2), 195).—A b s tra c t o f a p a p e r re a d before th e A m erican P h y sical Society.— S. G.
tB eryllium . (G adeau.) See p. 74.
*Specific R esistance of B ism uth Single Crystals [Effect of Im purities in Single Crystals]. A lfred B. F ocke a n d J o h n R . H ill (P hys. E ev., 1935, [ii], 48, (12), 973).— A b stra c t o f a p a p e r re a d before th e A m erican P h y sic a l Society. T he purposo o f th is in v estig atio n w as to s tu d y th e effect o f im p u rities in single cry stals. M easurem ents w ere m ad ę in th e ran g ę — 185° to + 100° C. on sam ples co n tain in g lead, tin , an tim o n y , a n d tellu riu m . T he effects w ere fo u n d to be com plicated, b u t th e follow ing generalizations m a y be m ade. D ecreasing -te m p e ra tu re re su lts in g re a te r effectiveness o f th e im p u rity p re se n t, ex cep t w hen th e co n ccn tratio n o f im p u rity is such t h a t a se p a ra tio n o f phases occurs a t Iow te m p e ra tu re s. E x tre m e ly sm ali a m o u n ts (less th a n 0-03% ) o f all im p u rities cause a sh a rp increase in th o resistance. T ho effect o f larg er am o u n ts depends on th e n a tu rę o f th e im p u rity . L ead a n d ti n co n tin u e to increase th o resistan ce, a d d itio n a l tellu riu m forces th e resistan ce to decrease to lower values th a n t h a t o f p u re b is m u th ; ad d itio n a l a n tim o n y causes th e in itia l increase o f resistance to decrease a n d th e n slow ly to be re-establisked. Moro th a n 0-03% tin a n d m ore th a n 0-3% le a d r e s u lt in a negative te m p e ra tu re coeff.
fo r th e resistan ce p arallel to th e p rin cip al axis. I n o th e r cases th e coeff. is positive. T h e re s u lts m ay be ex p lain ed q u a lita tiv e ly in th e lig h t o f preyious w ork o n th e m agnetic p ro p erties o f such c ry sta ls a n d th e d is trib u tio n o f im p u rities w ith in th em , to g e th e r w ith a s tu d y o f th e p h ase equilibrium dia- gram s fo r th e sy stem involved.— S. G.
♦D iam agnetism of th e T rivalent B ism uth ło n . S. S. B h a tn a g a r a n d B him S ain B a h l (Current S ci., 1935, 4, 153-154; G. A b s., 1936, 30, 339).—F ro m m easu rem en ts carried o u t on 10 o f its com pounds, yalues fo r th e diam agnetic
* Denotes a paper describing the results of original research.
t Denotes a first-elass critical review- G
70 M etallurgical Abstracts
Vo l. 3su scep tib ility o f tlie triv a le n t b ism u th ion are calculated. T he extrom e valucs f ° r -/A x 10° are 38-45 a n d 43-45, w ith 41-24 as th e m ean value. T he su scep ti
b ility is also calcu lated b y S la te r’s th e o ry to be 43-8. I t is p o in te d o u t th a t A ngus’s m odification o f S la te r’s m eth o d w ould give still b e tte r agreem ent betw een th eo retical a n d e sp e rim e n ta l resu lts.—S. G.
*The P lastic D eform ation of Cadinium Single-Crystals. R . R oscoe [Pliil.
M ag., 1936, [vii], 21, (140), 399-406).— O bservations o f th e bending o f single- c ry s ta l -wires show th a t , w hen th e stress over th o glide-planes o f a c ry s ta l is n o t uniform , slip begins w hen tho m a xim u m yalues o f th e resolved sh e a r stress reaches th e critioal valuo fo r deform ation u n d e r uniform stresses. Surface o x id atio n o f cadm ium single-crystals produces a n increase in th e ir resistan ce to p lastic deform ation, w hich is p ro b ab ly due to healing o f subm icroscopic craclcs b y th o oxide film .—J . S. G. T.
tO n th e Allotropy of Calcium. M. C. N eu b u rg er (Z. Elektrochem., 1935, 41, (11), 790).—F ro m th e re su lts h ith e rto o b tain ed , calcium possesses 3, n o t 4, allotropic m odifications. T he first h as a cubic face-centred la ttic e (A l ty p e ) ex istin g below 300° C., th e second betw een 300° a n d 450° C., a n d th e th ird w ith a hex ag o n al la ttic o (A3 ty p e ) is sta b le above 450° C__ J . H . W .
*The Photoelectrie W ork-F unction of Calcium an d Photo-Em ission from Non-Hom ogeneous Surfaces. N . C. Ja m iso n a n d R . J . C ashm an (P h y s. Rev., 1936, [ii], 49, (2), 201).—A b stra c t o f a p ap er re a d beforo th e A m erican P h y sical Society.—S. G.
♦The H ardness of Electrolytic Chrom ium . S. P . M akariew a a n d 3ST. D . Biriikoff (Z. Elektrochem., 1935, 41, (12), 828-842).— T he effect o f different conditions on th e hard n ess a n d h ydrogen c o n te n t o f electrodepositcd chrom ium w as in v estig ated : (a) b y th e ex am in atio n o f chrom ium deposits w ith a e u rre n t d e n sity o f 3-120 a m p ./d m .2; (1) th e h ard n ess curve o f different chrom ium deposits a fte r th o rom oval o f th e hy d ro g en show s b reak s w hich were c h a ra c te r
istic before th o rem o v al o f th e h y d ro g e n ; th e hard n ess o f th e chrom ium does n o t depond on tho h ydrogen c o n te n t; (2) th e m axim um yalue o f th e h ydrogen so lu b ility is reached a t 25 a m p ./d m .2, b u t th e h ard n ess o f th e m etal decreases as th o c u rrc n t'd e n s ity in e re a s e sfro m 7 to 1 20a m p ./d m .2; (b)b y d e te rm in in g th e te m p e ra tu re effect o n th e chrom ium d e p o sit; (1) tho so lu b ility o f h ydrogen in chrom ium inereases as th e te m p e ra tu re o f th e electroly te inereases to 35° C .;
from 35° to 40° C. i t decreases slig h tly , an d th e n ag ain ra p id ly in e re a se s; (2) th e hardness curves o f tho m e ta l a n d th o h ydrogen solubility curves do n o t go in th o sam e d irection u p to 30° C., b u t do so in th e in te rv a l 30°-40° C. becauso*
th e h ydrogen solubility as w ell as tho h ardness o f th e chrom ium are dep en d en t on a th ird facto r, such as th e grain-size o f th e d e p o s it; (3) a fte r th e rem o v al o f th e hydrogen, tho hardness curves o f different deposits rem ain n early u n altered , w hich is confirm ation t h a t th e hardness is in d ep en d e n t o f th e presence o f th e h ydrogen in chrom ium .— J . H . W .
Columbium and T antalum . Clarence W . B alke (In d u st. and E ng. Chem., 1935, 27, (10), 1166-1169).— E lectrolysis o f th e fused double fluorides o f th ese m etais (w ith potassium ) yields th e m etals in th e form o f fine crystaO ine pow der, w hich is liydraulically com pressed in to bars. These b ars are h eat- tr e a te d in v acu u m furnaces to p roduce ingots (n o t fused) w hich are ham - m ered, again h e a t-tre a te d , an d th e n w orked b y rolling o r draw ing. A ll w orking m u s t be done a t room te m p e ra tu re , as b o th m etals com bine w ith all com m on gases a t hig h te m p eratu res. T he sh eet m e ta l m ay be sp u n , draw n, o r co n v erted in to seam less tu b in g . E a b ric a te d ta n ta lu m is u sed in tho chem ical a n d ra y o n in d u stries, being ehem ically in e rt below 200° C. ex cep t in th o presence o f hydrofluoric a n d co n c e n tra te d sulphuric acids a n d stro n g alk alis. T a n ta lu m m ay be gas-hardened to a B rinell h ardness o f 600.
D egree o f h ardness a n d d e p th of p e n e tra tio n can be v aried th ro u g h w ide ranges.
B o th m etals a re being inereasingly u sed in th e e o n stru ctio n o f pow er a n d o th e r
1936
I . — Properties of M etals 71
vao u u m tu b e s. T lieir carbides liavo been in c o rp o rated in to a series o f com- positions fo r use as tools, dies, an d ab rasio n -resistin g surfaces.— F . J .
O xygen-Free Copper. H e n ry M. Sclileicher (W ire and W ire Products, 1935, 10, (11), 514-515).— A b rie f acc o u n t o f th e p ro p ertie s o f oxygen-free coppcr a n d o f th o h y d ro g en -an n eal te s t fo r th e absence o f oxygen in copper.— A. R . P .
*E xperim ental E esearches R elating to th e Surface Tension of M ercury a n d Its Alloys. M. L cm arch an d s a n d L. C onvers (J. Chim ie physique, 1935, 32, (9), 657-669).— T he dro p -w eig h t m eth o d w as em ployed to d eterm in e th e surface ten sio n o f m crcu ry a n d somo o f its alloys. T he v a lu e o f th e surfaco ten sio n o f m ercu ry in a ir a t 17° C., so d eterm in ed , is fou n d to dep en d o n th e r a te o f form a- tio n of th e dro p , decreasing fro m th e v alu e 494-3 to 445 dy n es/cm . as th e period o f fo rm atio n increased fro m 10 seconds to 28 m in u tes. T he cffect is possibly a ttrib u ta b le to th e ad so rp tio n o f im p u rities from tho air. I n a v acu u m , th e v alu e o f th e surface ten sio n o f m erc u ry is fo u n d to be p ra c tic a lly c o n s ta n t a n d to liave th o v a lu e 434 dy n es/cm . R e su lts o f exp erim en ts w ith calcium am al- gam suggest t h a t th o drop-w eight m e th o d is possibly u n su ita b le fo r th e d e te r
m in atio n o f th e surface ten sio n o f o th e r th a n p u re liquids.— J . S. G. T.
*The Longitudinal T herm oelectric Effect. V I.— M ercury. J . L. Ch’cn a n d W . B a n d (Proc. P liys. Soc., 1936, 48, (264), 164-167).— T he B encdicks e.m .f.
in m ercu ry co n tain ed in a n u n c o n stric te d glass tu b e is fo u n d to undergo a revorsible decreaso w ith inereasing te m p e ra tu re . I t is suggested t h a t th e re is a n aniso tro p ic ąu asi-ery stallin e a rra n g e m e n t o f th e surface m oleeules o f m ercury w hich is d e p e n d e n t on te m p e ra tu re . Q u a n tita tiv o a n aly sis o f th e te m p e ra tu re d is trib u tio n failed to give th e liom ogcncous coeffs., p resu m ab ly because th e effect o f te m p e ra tu ro on th e c o n sta n ts is v e ry m ark ed .— J . T .
*M agnetic Inversion P oints by th e D iffusion of H ydrogen T hrough Nickel and Iro n a n d T hrough Iro n -N ick el an d P alladium -N ickel Alloys. W . R . H a m a n d J . D . S a u te r (Pliys. ltev., 1936, [ii], 49, (2), 195).— A b s tra c t o f a p a p e r re a d before th o A m erican P h y sical Socicty. T ho diffusion o f hy d ro g en th ro u g h hom ogeneous m etals follows th e fo rm u ła R = A [(p0v — p l'/)/X]Te~l,IT, w here R is th e x-ate o f diffusion, A is a c o n s ta n t o f th e diffusing m etal, p 0 a n d p , are pressures on ingoing a n d outgoing sides, y is a v a ria b le e x p o n e n t o ften n early 0-5, T is th e te m p e ra tu re K elv in , X is tho th ick n ess o f diffusing sh eet, a n d b is tho to ta l w ork-function exprcsscd in eq u iv alen t degrees. 0 ver a rangę betw een 200° a n d 800° C. th o iso th erm s fo r th e m etals m entioncd in th o title a rc alm o st lin ear betw een pressures o f 74 cm . a n d 1 cm . o f m ercu ry , b u t tho slopes (y) are n o t necessarily c o n s ta n t w ith te m p e ra tu re change, n o r a re th e isó b ars ncces- sa rily linear. P u re nickel show s a d is e o n tin u ity in diffusion iso b ars a t 360° C.
w hich c a n n o t bo m istak en , as does also p allad iu m slig h tly alloyed w ith nickel.
Tho cooling curves a n d m agnotom eter curvcs fo r nickel show th e m agnetic inversion to be v e ry n e a rly a t th is sam e p o in t. In th e case o f iro n alloyed w ith nickel, th e iso b ars show a sh a rp change in slope a b o u t 600° C., w hereas p u re iron show s a large change in its iso b ars beginning a t 760° C. T he energy clianges involvcd in these m agnetic tra n sfo rm a tio n s a re discussed.— S. G.
*Phenom enon of N egative H ysteresis in Nickel. S. S h a ra n (Currcnt S ci., 1935, 4, 157; C. A b s., 1936, 30, 338).— Specim ens o f nickel w ire w ere first carried th ro u g h a few com plete m ag n etizatio n cycles a n d th e n lo ft in a w eak field to produce a sm ali p o sitiv e m ag n etizatio n while a lte m a tin g fields w ere applied. L o n g itu d in al a lte m a tin g fields p ro d u ced effects sim ilar to those in iro n . C ircular a lte m a tin g fields, pro d u ced b y passing a n a.c. th ro u g h th e specim en itsolf, b ro u g h t o u t th e phenom enon o f n eg ativ e h ysteresis, sim ilar to effects obscrved in stu d ies o f tho m agneto-resistanco change in nickel. S.
d ire c ts a tte n tio n to th e fa c t t h a t in b o th cases tho nickel is carry in g e u rre n t, so t h a t th e effect m a y be associated w ith m oyem ent o f th e conduction elcctrons.
— S. G.
72 Metallurgical Abstracts
Vo l. 3*The Therm om agnetic Properties o£ Niekel.—II . W illiam B a n d a n d Y . K . H sii (Proc. P hys. Soc., 1936, 48, (264), 168-177).—Tho hom ogeneous therm o- eleotric o.m.f. in niekel is exam ined fo r yario u s tensions u p to 8 kg. in a w ire o f puro niekel o f d iam eter 1 m m . A nalysis gives th e B enedicks’ eoeffs. as func- tio n s o f th e m agnotic field a n d tension. A n an ti-sy m m etrie p a r t o f th e e.m .f.
w ith resp eet to th o m ag n etizatio n is found. I t is suggested t h a t th e effect n iay be eontrolled by th e re g u la rity o r an iso tro p y o f arra n g e m e n t o f m icro- e ry sta ls w ith in th e w ire.— J . S. G. T.
*The Surface Ionization of P otassium on T ungsten. M. J . Coplcy a n d T . E . P h ip p s (Phys. liev., 1935, [ii], 48, (12), 960-968).—S. G.
*The Absolute M easurem ent of th e Viscosity of Liąuid Tin. A. J . Lewis (Proc. P hys. Soc., 1936, 48, (264), 102-110)__ V alues o f th e viscosity (yj) o f liq u id ti n were d eterm in ed b y th e cap illary -tu b e m eth o d betw een 235° an d 330° C. Tho yalues o f (y j), m easured in poises, fo u n d w ere : 235° C., 0 0195;
240° C., 0-0192; 250° C., 0-0186; 260° C., 0-0181; 270° C., 0-0176; 280° C., 0-0173; 290° C., 0 0170; 300° C., 0-0167; 310° C., 0-0164; 320° C., 0-0162;
330° C., 0 0160. These yalues are in good agreem en t w ith those o b tain ed by S to tt, a n d confirm th e g enerał accu racy o f th e w ork o f S auerw ald a n d T opler.
T he te m p e ra tu re y a ria tio n o f y iscosity a n d th e valuo o f th e viscosity a t th e freczing-point aro a d e q u a te ly rep resen ted b y A n d rad e’s th eo ry .
— J . S. G. T.
♦Correlation of Em ission an d A dsorption Properties w ith L attice D irection in Single Crystal Tungsten W ire. W . Shockley a n d R . P . Jo h n so n (Phys. Rev., 1935, [ii], 48, (12), 973).— A b stra c t o f a p ap er re a d before th e A m erican P h y sic a l Society. In v estig atio n o f single c ry s ta l tu n g s te n w ires b y m eans o f a n electron microscope arran g em en t (Johnson a n d Shockley, ibid., p . 973) reyeals a m arked correlation betw een crystallographie d irection in th e la ttic e a n d th e em ission a n d a d so rp tio n p ro p erties o f th e surface. Single c ry sta ls grow n b y lie a t-tre a tm e n t in a d raw n w ire o f p u re tu n g ste n , h ay in g th e 110 d irection along th o w ire axis, give a p a tte rn w ith a m inim um a b o u t 20° b ro ad a b o u t tho 110 directio n , a n d m inim a a b o u t 5° b ro ad in direetions 60° from 110. C ry stal o rien tatio n s arę d eterm in ed from L aue p ictu res o f th e wiro a f te r i t has been rem oyed from tho tu b e. W hen th o lilam en t is ru n a t low te m p e ra tu re s in eąu ilib riu m w ith s a tu ra te d caesium v a p o u r a t room te m p e ra tu re th e c o n tra st betw een lig h t a n d d a rk regions on th e tu b e w ali is m uch m ore m ark ed , a n d th e p a tte r n goes th ro u g h a y a rie ty o f phases as th o filam ent te m p e ra tu re is changed o v er th e o b serv atio n ran g ę 700°-900° K . I n generał, direetions o f m inim um em ission from clean tu n g ste n aro direetions o f large em ission from th e cassium - tu n g s te n surface. T here is, liowever, m uch m ore “ fine s tru c tu re ” in th e eoesium -tungsten p a tte rn s, regions less th a n 5° a p a r t on th e w ire circum ference differing m ark ed ly in electron em ission a n d therefo re p resu m ab ły in equili- b riu m covcrago o f caisium. I n every case th e em ission p a tte r n ex h ib its tho tw o reflection planes, 100 a n d 110, o f th o tu n g s te n single c ry s ta l, a n d th e p a tte r n reproduces itse lf in each q u a d ra n t dow n to th e sm allest observablo d etail. E x p erim en ts w ith p o ta s siu m -tu n g ste n surfaces a n d w itli com posito layers give sim ilar resu lts. P relim in ary in y estig atio n s o f single c ry s ta l tu n g ste n w ires grow n b y th e P in tsc h process, w hich gives c ry sta ls o f ran d o m o rien tatio n , in d icate th e possibility o f m apping o u t em ission a n d ad so rp tio n p ro p erties over th e e n tirc gro u p o f la ttic e direetions in tu n g s te n a n d in o th e r m etals w hich can be o b tain ed in th e form o f sm ali single c ry s ta l w ire.—S . G.
*The G rowth of Metal Crystals in M etal V apours [Tellurium ].— IV. M.
S tra u m a n is (Z. physikal. Chem., 1935, [B], 30, (2/3), 132-138).—S u b lim atio n ex p erim en ts were earried o u t w ith tellu riu m a t yario u s pressures b o th below a n d above th e m elting p o in t to te s t th e y a lid ity o f K ossel a n d S tra n sk i’s th e o ry o f hom opolar cry sta l g row th. T he c ry sta ls o b tain ed w ere m easured a n d th e ir equilibrium form determ ined.— K . S.
1936
I I . — Properties of A lloys 73
An A pparent R egularity in /3-Ray Reflection. Sam uel C. C u rran (P hil. M ag., 1936, [vii], 21, (140), 406-415).— D iffraction rings, o b tain o d b y th e m ultiple- sc a tte rin g o f j3-rays fro m th in films o f b rass, lead, copper, iro n , alu m in iu m , a n d carbon, are show n to be a ttrib u ta b lo to refiected /3-particlcs h ay in g velocitics a p p ro x im a te ly tho sanie as th o in c id e n t p a rtic le s ; th e re s u lts can bo u sed to deduce th e re la tiy c reflecting pow ers o f m a te ria ls __ J . S. G. T .
I I .— P R O P E R T IE S O F ALLOYS
(Continued from pp. 3G-39.)
*D ensity Changes in Solid A lum inium Alloys. L . W . K e m p f a n d H . L.
H o p k in s (M etals Technology, 1936, 3, (1), 1 -1 6 ; Tech. P ubl. N o. 671).— Tho
“ gro w th ” o f a lu m in iu m alloys on re h e a tin g in th e ran g ę 175°-230° C. follow- ing ra p id cooling from a so lu tio n h e a t-tre a tm e n t is in v estig ated . T h e “ g ro w th ” yaries betw een 0 a n d 0-16% according to com position a n d h e a t-tre a tm e n t.
T he r a to o f “ g ro w th ” u n d e r iso th c rm a l conditions depends largely on com position. T h e a tta in m e n t o f m ax im u m “ gro w th ” re ą u ire s m u ch longcr periods o f tim e th a n th e a tta in m e n t o f m a s im u m hard n ess.— J . S. G. T.
*A lum inium -M agnesium Alloys. P ie rre V ach et (Rev. M U ., 1935, 32, (12), 6 1 4 -6 2 6 ; a n d Rev. A lu m in iu m , 1935, 12, (76), 3087-3099).—V. d eterm in ed th o la ttic o spacing o f tho cc m ag n esiu m -alu m in iu m solid so lution fo r 8 a n d 12% m agnesium . A d d itio n o f m anganese d id n o t affect “ a ” appreciably.
E ffects o f an n ealin g a n d ąu en ch in g a re s tu d ie d for alloys co n tain in g from 5 to 13% m agnesium w ith a n d w ith o u t a n a d d itio n o f 0-5% m anganese.
D iffieulty is experienced in p re c ip ita tin g tho /J-phaso from solid solution co n tain in g less th a n S% m agnesium . T he alloys w ere su b jected to m echanical te s ts in y ario u s conditions. Q uenching from 450° C. gives m o d erate stre n g th a n d a useful degree o f d u c tility as show n b y elongation yalues. R eh eatin g th e ąu en ch ed alloys to 150° o r 200° C. giyes in somo cases a sliglit increase in tensilo stre n g th , b u t tre a tm e n t fo r long periods causes a considerablc red u ctio n in elongation yalu e. Corrosion p ro p ertie s a re stu d ie d b y change in tensile p ro p ertie s. (Juenched sam plcs a n d “ as rollcd ” sam ples sliowcd v e ry slow d eterio ratio n , b u t an n ealed a n d ąuenclicd a n d tem p ered sam ples d e te rio ra te d moro ra p id ly . Tho p ro p ertie s o f c a s t a n d c a s t-h e a t-tre a te d bars are exam ined.—H . S.
*Optical Changes in Freshly E vaporated A lum inium -M agnesium F ilm s. H ira m W . E d w ard s a n d R o b e rt P . P e te rse n (P hys. R ev., 1936, [ii], 49, (2), 207).—
A b s tra c t o f a p a p e r re a d beforo th o A m erican P h y sical Society. D eals w ith a s tu d y o f reflection a n d tran sm issio n ch aracteristics o f fresh ly e v a p o ratcd fllms o f a n alu m in iu m -m ag n esiu m alloy. A p p a ra tu s w as arra n g e d inside a n e v ap o ratio n c h am b e r so t h a t m easurem ents could bo m ad e d u rin g a n d a fte r deposition o f th e m etallic fihn. T hrco ty p es o f changes in reflection a n d tr a n s m ission coeffs. w ere obseryed : (1) O ccurring a t pressures o f 10~4 m m . o r less.
T h is consists o f a sm ali, ra p id decrease in reflectiy ity a n d a n inereaso in tra n s- m issiyity. Ono m inuto is re ą u ire d fo r th is change. T he tran sm issio n coeff.
a lte rs moro ra p id ly th a n th o reflection coeff. N o fu rth e r effect ta k e s place in tho y acuum . (2) T ho sccond ty p o occurs durin g tho adm ission o f a ir o r n itro g en in to tho v acu u m cham ber. I t consists o f a decrease in reflectiy ity a n d a n inereaso in tra n sm issiv ity . T h e ra to o f change is defuiitely d ep en d en t o n th e ra to o f increase o f pressure in th o y acu u m cham ber. (3) T h is ty p e ta k e s place y e ry slowly, ov er a period o f seyeral d a y s. Tho finał y alu e o f th e reflec
tio n o r tran sm issio n coeff. is ap p ro aclied asy m p to tically . T he m ag n itu d es o f th e 3 ty p e s o f changes for a film hay in g a n in itia l reflection coeff. o f 58% w ere obseryed to bo 8, 5, a n d 10% , respectively, a n d fo r a n o th e r film h ay in g a n in itia l tran sm issio n coeff. o f 35% th e y w ere 5, 8, a n d 5 % .— S. G.
74 M etallurgical A bstrads
Vo l. 3fB eryllium . R . G adeau (Rev. M il., 1935, 32, (12), 627-G37).— T he occur- rence, ex tra c tio n , a n d p ro p erties o f beryllium are discussed. T h e p ro p erties a n d m ain featu res o f tho b in ary alloys o f beryllium w ith alum inium , niekel, iro n , a n d copper, aro described, spccial rcference being m ade to b ery lliu m - bronze (2-3% beryllium ).— H . S.
A New Low-M elting Alloy. Sidney J . F re n c h (In d u s t. a nd E ng. Gliem., 1935, 27, (12), 1464-1465).— Tho fusible qu a te rn a ry eu tectic alloy u su ally te rm e d th o “ L ipow itz eutectic alloy ” (b ism uth 50, lead 27, tin 13, cadm ium 10% ) m elts sh a rp ly a t 72° C. a n d freezes a t 70° C. Q u in tcrn ary alloys w ere p rep ared b y a d d in g indium to th e above-m cntioned alloy. T he freezing ranges o f these alloys are ta b u la te d . T he ad d itio n o f 18-1% in d iu m to th o Lipow itz alloy resu lted in th o freezing-point being low ered to 46-5° C. I t s com position is b is m u th 40-95, lead 22-11, indium 18-10, tin 10-65, cadm ium 8-20% . T he cost o f th is alloy w ould be $5 p er oz. in sm ali lots. T he h u m a n b o d y c a n como in to c o n ta c t w ith th o m olten alloy w ith o u t d isc o m fo rt; i t w ould therefo re be suitablo fo r m aking ea sts o f featu res a n d finger-print im pressions a n d fo r sur- gical w ork. I t oxidizcs v e ry little in th e m olten S tate, being th u s su p erio r to wood, m etal, a n d Lipow itz alloy.— F . J .
♦The A bnorm al P henom enon of Cast Copper-Rich Copper-Silicon Alloys D uring H eating. T a k u m i T a k o ta n i a n d S ab u ro K a to ri (N ip p o n Iiw agaku K toaishi (•/. Chem. Soc. J a p a n ), 1935, 56, (9), 105S-1064; C. A b s., 1936, 30, 65).— [In Jap an ese.] Tlie a b n o rm al th e rm a l expansion whioh ta k e s place on heatin g th e c a s t copper-silicon alloys co ntaining 3-0-7-5% Silicon a t 200°- 800° C. w as stu d ie d . Tho phenom enon is a ttrib u te d to th e hom ogenization o f th e a-phasc, a n d th e solution o f th e fi-phase in to th e a-pliase as solid solution.
— S. G.
♦The H om ogenization of Cast S tructures in Copper-Rich Copper-Silicon Alloys.
T ak u m i T a k e ta n i (N ip p o n K w agaku K w aislii (J. Chem. Soc. Ja p a n ), 1935, 56, (9), 1064-1071; C. A b s., 1936, 30, 65).— [I n Jap an ese.] Cf. preceding a b s tra c t. W ith increase o f Silicon c o n te n t th o te m p e ra tu ro re ą u ire d to bring a b o u t hom ogenization o f th e a-pliase becom cs low er a n d th e ten d en cy o f th e j3-phase to rem ain undissolved b y heatin g pred o m in ates.—S. G.
T ungum Alloy. --- (A lu m in iu m and N on-F errous Rev., 1935, 1, (3), 115-116).— D escribes tho physical, m echanical, a n d corrosion-resisting char- a ctc ristics o f tliis non-ferrous alloy (com position n o t given).— J . C. C.
*Electrical Conduetivity a n d Equilibrium D iagram of B inary Alloys. The L ithium -A lum inium System. G. G rube, L . M ohr, a n d W . B reuning (Z.
Eleklrochem., 1935, 41, (12), 8 8 0 -8 8 3 ; a n d (a b s tra c t) L ight M etals Research, 1936, 4, (14), 230).— T he cąuilibrium diag ram o f th e system lith iu m -alu m in - ium was in v estig atcd b y th e rm a l an aly sis a n d te m p e ra tu re -rc sista n c e curyos o f tho solid alloys. Tho fluid m etals are n o t m u tu ally solublo in a ll pro p o rtio n s, b u t a g ap occurs in th e fluid s ta te ex ten d in g from 44-5 to 60-0 ato m ic-%
lith iu m a t 698° C. T ho lim itin g co n cen tratio n o f th e a-solid solution on th e alum inium -side w as d eterm in ed betw een 600° C. a n d room te m p e ra tu re b y c o n d u c tm ty m easurom ents. T he in term ed iato c ry s ta l form , LiA l, fo u n d b y A. M uller (Z. M etallkunde, 1926,18, 231), a n d described as to its stru c tu ro b y Z in tl a n d W oltorsdorf (M et. A bs., th is vol., p. 76), form s, w ith exccss lith iu m , tho jS-solid solution, whoso ran g ę o f hom ogeneity a t 521° C. e x ten d s from 50 to 56 ato m ic-% o f lithium . T he existenco o f th e c ry s ta l form , L i2Al, was d e te c te d ; i t ia form ed a t 521° C. by th e p eritectic reactio n betw een th e /S-solid so lu tio n a n d th e m e lt__ J . H . W .
*X -R ay Analysis of th e L ithium -Z inc Alloys. (Z intl a n d Schneider.) Seo p. 77.
*E xperim ental R esearches R elating to the Surface Tension of M ercury and Its Alloys. (L em archands a n d C onvers.) See p . 71.
K Monel. W . A. M udge a n d P . D . M erica (Ja p a n N iekel R ev., 1935, 3, (4), 506-512).— [In E nglish a n d Ja p an ese.] A n an aly sis o f a ty p ic a l m ateriał
1936
I I I . — Structure 75
is nickel 63-32, copper 30-84, a lu m in iu m 3-45, iro n 1-50, m angancse 0-50, carbon 0-16, Silicon 0-20, su lp h u r 0 005% . Tlie alloy can be h ard cn ed b y lieat- tr e a tm e n t a n d is p ro d u ced in fo u r d ifiere n t degrees o f hardnoss, th e hig h est having a B rinell nuinber o f 325. A n y grado m ay be softened b y heating to 760° C. a n d th e n ąuencliing in w a te r o r oil. T he alloy re ta in s its p ro p ertie s a t m o d erately eley a ted te m p e ra tu re s.— W . A. C. N .
♦A ceelcrated Servioe Tests of P in tle B earings. A m brose H . S ta n g a n d L ero y R . S w eetm an (./. Research N a t. B u r. S ta n d ., 1935, 15, (6), 5 9 1 -6 0 0 ; Research P aper N o. 8 5 4 ; a n d (a b stra c t) M ech. W orld, 1936, 99, (2565), 219-220).—
A ccelerated service te s ts o f p in tle bearings w ith d ifiere n t co m binations o f m aterials fo r th e p in tle s a n d cups, d ifiere n t pressures, a n d d ifiere n t con- ditio n s o f lu b ric a tio n woro m ade u n d e r conditions sim ilar to th o se w hich m ig h t o b ta in in p ractice as to th e lino o f th r u s t a n d anglo o f sw ing. Tho bearings wore u n d e r w a tc r d u rin g th o te s ts . Tho re s u lts in d ic a te d t h a t o f tho m aterials to s te d ono m u s t be p h o sp h o r-b ro n ze to give sa tisfa c to ry sorvico fo r pressures as g re a t as 2000 lb ./in .2. P in tle s o f H-M onel, M-Monel, a n d S-M onel gavc sa tisfa c to ry sorvico a t th is pressuro w ith p h o sp h o r-b ro n ze cups. Cups o f stainless steel, ch ro m iu m -steel, ch ro m iu m -n ick el steel, m alleablo c a s t iron, a n d M onel alloys w ere scored b ad ly a fte r only a few cycles w hen tc s te d u n d e r a pressure o f 2000 lb ./in .2. A lu m in iu m -" bronzo ” cups w ere w orn excessively a t a co m p arativ ely sm ali n u m b e r o f cycles. P h o sp h o r-b ro n ze w as th e only cu p m a te ria ł te s te d in th is in v estig atio n w hich gave sa tisfa c to ry seryico w ith a pressure as g re a t as 2000 lb ./in .2. A stainless steel p in tle a n d p h o sphor-bronzo cup p rovided w ith grooves for w ater circu latio n a n d te s te d u n d e r a p ressu re o f 4000 lb ./in .2 w ith sto o d moro th a n 288,000 cycles, th e n u m b e r o f cycles ex- p c c te d in 20 y o ars’ service. A stain less steel p in tle a n d p h o sp h o r-b ro n ze cup lu b ric a te d w ith w bito lead o r w ith grease liaving a lea d -so a p baso a n d a s p h a lt c o n te n t d id n o t fail w hen te s te d u n d e r a pressure o f 6000 lb ./in .2 a n d su b jected to m ore th a n 288,000 cycles.— S. G.
New Alloys. T . W . L ip p e rt (Iro n Age, 1936,137, (1), 171-182).— D escribes low -alloy, high-tensile steels, developm ents in non-ferrous m ctallu rg y du rin g 1935, now h e atin g elem ents, free-m achining alu m in iu m , new M onel alloys, borido alloys, a n d o th e r now allo y s__ J . H . W .
fT w o-D im ensional D iagram s. L . G ren et (M ela u x, 1935, 10, (123), 2 4 8 - 263).— R cad a t th o 7e. Congros In te rn a tio n a l des M ines, de la M ćtallurgio e t do la Gćologie ap p liąu će. T he applioation o f th e P h a se R u le to th e co n stru ctio n o f 2-dim ensional e ą u ilib riu m d iagram s, th o d is tin c tio n betw een ehom ical a n d physical o r m eehanical eąu ilib riu m , a n d th o conception o f th e te rm “ p h ase ” aro discussed. E ą u ilib riu m d iag ram s w ith 2 v ariab les, th e in te rp re ta tio n o f b in a ry diagram s, a n d d iag ram s o f 2 variab les a d m ittin g o f tho oxistence o f a n u m b e r o f m asses u n d e r e o n stra in t, aro exp lain ed a n d illu s tra te d .—J . H . W .
I I I .— STR U C TU R E
(M etallo g rap h y ; M a cro g rap h y ; C rystal S tru ctu re.)
( Continu ed from pp. 39-41.)
*A Method for Obtaining Perfectly Polished M etallic Surfaces. P ierre J a c ą u e t (Com.pt. rend., 1935, 201, (27), 1473-1475).— P olishing m e ta l surfaces by m echanical ab rasio n leaves scratches a n d a th in film o f a s tru c tu re d ifiere n t from t h a t o f th e su b ja c e n t m etal. Good re su lts h av e been o b tain ed w ith copper a n d c e rta in o f its alloys b y a tta c k in g th e m e ta l anodically in a co n c e n tra te d aąu eo u s so lu tio n o f o rth o - o r p y ro-phosphorie acid. T he so lu tio n co n tain s 400 g rm ./
litre o f th e acid a n d is k e p t a t 15°-25° C. T he cath o d o is a cop p er p la te o f la rg e r surface th a n th e anodę. A n am m eter, a v o ltm e te r, a n d a variablo resistan ce com plete th e circu it. T he Y o lę a g e u sed depends on th e co n cen tratio n o f th e so lution a n d especially on th o po sitio n o f tho anodę, a n d is t h a t a t w hich
76 M etallurgical Abstracts
Vol. 3th e evolution o f gas ap p ears. T he solutions m u s t be filtered, a n d th e fine bubbles o f gas, w hich som etim es a p p e a r on th e m e ta l w hen i t is im m ersed, m u s t be elim inated.— J . H . W .
♦The A nisotropic G row th of Silver Crystals by Condensation from V apour.
Jo s e p h H . H ow ey(PA i/s. liev., 1936, [ii], 49, (2), 200).— A b s tr a c to f a p a p e r r e a d before th e A m erican P h y sical Society. I t h as been fo u n d t h a t silver v a p o u r condensing in a v acuum o n su itab le nuclei o f solid silver m a in ta in e d a t a te m p e ra tu ro j u s t below th e m elting p o in t form s single c ry s ta l needles u n d e r c e rta in conditions. T he o b se rre d h a b it o f g ro w th is p ro b ab ly d e p e n d e n t on th e presence o f c e rta in im purities, b u t i t is n o te w o rth y t h a t a m e ta l h av in g faee-centred cubic sy m m e try in th e solid s ta te sh ould e v er condense in th e form o f needles. T he longest needles grow n w ere a b o u t 3 m m . long a n d several te n th s o f a m m . in diam eter. A t le a s t 5 % o f th e needles h a v e a b r u p t changes in directio n , th e ap p earan ce o f w hich in d icates t h a t th e b o u n d a ry betw een th e tw o lin ear p o rtio n s coincides closely w ith a single crystallographic p ian e e ste n d - ing across th e en tire cross-section. A b ru p t changes in d irection b o th less a n d g re a te r th a n 90° h av e been observed, b u t no b ranching has been found. One te n t a ti r e e x p lan a tio n o f th e g ro w th o f th ese needles is to consider th e ir occur- rence as e x p erim en tal evidence fo r th e id ea t h a t th e forces betw een m etal ato m s in a c ry s ta l m ay be g re a te r in one d irectio n th a n in o th ers w hich are crystallo g rap h ically id en tical a n d th a t th e d irectio n o f th is an iso tro p y m ay be c o n s ta n t th ro u g h o u t a d om ain o f considerable size. T he existence o f such a n iso tro p y w ould serve to ex p lain th e g ro w th o f th e needles regardless o f w h eth er th e g ro w th is conditioned by th e presence o f im p u rities o r n o t.— S. G.
tT h e Structure of Some Copper Alloys. W . B roniew ski (Rev. M et., 1935, 32, (12), 649-657).— A s u r re y o f th e re su lts o f stru c tu ra l in y estig atio n s o f b in a ry alloys o f copper w ith nickel, alum inium , zinc, tin , a n d gold.— H . S.
*The S tru ctu re of th e Z inc-C adm ium E utectic. 51. S tra u m a n is a n d jST. B rak śs (Z. ph ysika l. Chem., 1935, [B], 30, (2/3), 117-131).—T he zinc-cadm ium eu tec tic consists o f relativ ely coarse fibres w hich can be o b se rre d a t Iow m agnifications.
T hese fibres are n o t hom ogeneous b u t are b u ilt u p o f layers to p roduce a tru e eu tec tic s tru c tu re w hich is resolved a t high m agnifications.—K . S.
*X -Ray Study of Iron-N ickel Alloys. E rie R . J e t t e a n d F ra n k F o o tc (M etals Technology, 1936,3, (1), 1 -1 4 ; Tech. P vb l. N o. 670).—T he resu lts are given o f a n X -ra y in v estig atio n o f 15 iro n -n ick e l alloys, w ith a n u m b er o f h e a t-tre a t- m ents. T he y-phase (face-centred cubic) alloy la ttic e c o n sta n ts w ere d eter- m ined over th e rangę 2 5 -1 0 0 % nickel w here th is phase could be re ta in e d in ta c t by d ra s tic ąuenching. P o sitiv e large dev iatio n s from th e a d d i t m t y ru le w ere fo u n d . T he m axim um la ttic e c o n sta n t w as fou n d a t a b o u t 35 ato m ic-%
nickel. F ro m 100 to 43 a to m ic-% nickel th e la ttic e c o n s ta n t a w as given b y a — 3-64033 — 0-0012379^’, w here N i s th e pereentage (atom ie) o f nickel. T he value o f a decreases sh arp ly from its m axim um value, a n d from 0 to 20%
nickel i t ex tra p o la te s lin early to 0 h m a n ’s value fo r p u re y-iron. T he a-phase ran g ę u p to a b o u t 5 ato m ic-% nickel sim ilarly show ed m ark ed positiye devia- tions from th e a d d itiv ity n ile. T e n ta tiv e lim its fo r th e tw o-phase region are suggested. X o in d icatio n w as o b ta in e d o f th e existence o f com pounds o r su p erstru ctu res. A ta b le o f densities o f th e alloys c alc u lated from th e la ttic e c o n sta n ts is given.—J . S. G. T.
♦Lattice S tructure of L ithium -A lum inium . E . Z in tl a n d G. W o ltersd o rf (Z. Elektrochem., 1935, 41, (12), 876-879); a n d (sum m ary) L ighl M etals R e search, 1936, 4, (14), 228-229).— L ith iu m -alu m in iu m alloys were m elted u n d er lith iu m fluoride in arg o n in a zirconia crucible from th e com ponents. X -ra y an aly sis show ed only th e in term ed iate p h ase LiA l in th e ran g ę 0 -5 0 ato m ic-%
lith iu m . A lum inium s a tu ra te d w ith lith iu m h a s th e la rg e st la ttic e dim ensions, b u t th e w idening o f th e la ttic e is less th a n t h a t to be expected from th e addi- tiv ity o f th e atom ie rad iu s. L iA l haę a cubic body -cen tred la ttic e o f th e N aT l
1936
I I I . — Structure 77
type, w ith a = 6-360 A. F ro m tho lattico in te rv a l a n d tho fao t t h a t espeeially elom ents w ith 3 valency electrons w ith lith iu m o r sodium form N aT l struoturos in w hich th e n o b ler a to m s form a diam o n d la ttic e , a concoption o f th e reciprocal effect o f th e ato m s in such s tru c tu re s w as d erived as a w orking h ypothesis for fu rth er in v estig atio n s.— J . H . W .
♦X-Ray Analysis of th e L ithium A m algam s. E . Z in tl a n d A. Schneider (Z . Elektrochem., 1935, 41, (11), 771-774).—Tho re su lts o f X -ra y analysis agreed w ith those o f therm o-analysis, in t h a t in th o sy stem lith iu m -m e rc u ry a t room tem peraturo in th o rango 0 -7 8 ato m ic-% lith iu m , 5 in tcrm ed iato phases occurred, hav in g th o ap p ro x im ato com positions L iH g3, L iH g 2, L illg , L i2IIg , an d L ijH g. T he stru c tu re o f 2 o f these phases, viz. L iH g , a n d L i2H g , could n o t be clcared u p . F ro m revolving c ry stal, goniom eter a n d pow der d iagram s o f L iH gj, a hoxagonal elom ont w as found w ith a= G -240 A ., c= 4 -7 9 4 A ., an d c /a — 0-768. I t co n tain s 2 ato m s o f lith iu m in th e planes 0 0 0 a n d $•■§£, a n d 6 atom s o f m ercury in th o planes J 0 0, 0 £ 0, £ £ 0, $ £ £, $ $ £, a n d }j § Tho lattico o f L iH g3 is a n o v e rstru c tu re o f th o hoxagonal den sest sphere packing.
LiH g has th e stru c tu ro o f /S-brass w ith a — 3-287 A. T he pow der diag ram of Li3H g in d ieates a cubic la ttic e w ith a = 6-584 A ., face-centred tra n sla tio n group, w ith 4 m ercu ry a n d 12 lith iu m ato m s p e r celi. Li3H g h as tho samo stru c tu re as Cu3A1, th e /3-phase o f th e coppor-alum inium system .— ,T. H . W .
*X -Ray A nalysis of th e L ithium -Z inc Alloys. E . Z in tl a n d A. Schneider (Z.
Elektrochem., 1935,41, ( 11), 764-767) X -ra y inv o stig atio n o f tho lith iu m -zin o alloys by th e pow der m eth o d essentially confirm ed th e re su lts o f G rubo a n d V osskuhler (M et. A bs., 1 9 3 4 ,1 ,1 2 5 ), w ho found 5 in term ed iatc cry s ta l form s a t room tem p eratu ro . Tho /3'-phase w ith a b o u t 10 ato m ie-% lith iu m has a hexagonal lattico w ith th e d ensest sphere packing, a — 2-782 A ., c = 4-385 A., c/a = 1-576, a n d s ta tic ato m ie arran g o m en t. F o r th e y'-phaso w ith a b o u t 28 ato m ic-% lith iu m , a hexagonal psoudo-cell w ith a = 4-362, c == 2-510, an d c/a = 0-575 is suggested, w ith 2 zinc ato m s on tho 0 0 0 a n d J § Ą- planes. Tho 8"-phaso (LiZn) has a cubic stru c tu ro o f tho N aT l ty p e , w ith a = 6-209 A.
— J . H . W .
*Structure of th e P latin u m -T h alliu m Alloys. E . Z in tl a n d A. I la rd e r (Z.
Elektrochem., 1935, 41, (11), 767-771).— P la tin u m ta k e s u p littlo th alliu m w ith a w idening o f th e lattico o f a b o u t 1 -5% ; conyersely, th e solubility o f p latin u m in th alliu m appoars to bo v e ry Iow. B o th m etals form only ono in tcrm ed iato cry stal form w ith tho form uła P tT l, whoso stru c tu ro has been d eterm ined by layer-line, goniom eter, a n d pow der diagram s. I t has a hexagonal lattico, a = 5-605, c = 4-639, c /a = 0-828, w ith 6 ato m s p e r celi on th o following planes : 0 0 0, £ ^ 0, & 0 0, 0 & 0, £ § £ , § £ $. O n acco u n t o f tho a lm o st cqual seatterin g o f p la tin u m a n d th a lliu m , i t c a n n o t bo dccided w hether b o th kinds o f ato m s are reg u lar o r d is trib u te d on tho lattico p o in t. T hallium form s no com pound w ith p la tin u m w ith th o nickel arsenido s tru c tu re . A proccss is described for th e p ro d u ctio n o f sm ali a m o u n ts o f th e alloys from tho p artly high m elting an d p a rtly yolatilo com pononts. Tho m etals aro h c a te d under argon in a sin tered corundum cruciblo w liich is m ado g a s-tig h t w ith a n oxy- acetylene flam e.— J . H . W .
tS tu d y of Metallic Crystals. ^ E . Schm id (lłev. M il., 1935, 32, (12), 638-648).
— A su rv ey o f tho resu lts o f X -ra y stu d ies o f tho s tru c tu re s o f singlo crystals.
A tte n tio n is given to p hysical p ro p erties in different dircctions, p lastic deform a
tion, se p aratio n o f a c o n stitu e n t from a s a tu ra te d phaso, a n d relationship betw een p ro p erties o f aggregates a n d single cry stals. A slio rt bibliography is ap p en d ed .— H . S.
♦The H um e-E othery Conception of th e Metallic State. C. D . N iven (Phil.
M ag., 1936, [vii], 21, (139); 291-299).— I t is considered t h a t H u m o -R o th c iy ’s (8 — N ) rule fo r tho m etallic sta to is m ore clcarly s ta te d th u s : In crystallizing, each a to m has (8 — N ) n ear neighbours, w hero N is tho num bor o f electrons in
78 M etallurgical Abstracts
V o l . 3 th o “ p ” sy stem . Tho u n iąu o caso o f b ism u th is assoeiatcd w ith 6 sh ared oloctrons. Tho plicnom ena o f m etallic conduetion a n d o f su perconduction aro oxplained in tc rm s o f tr a n s it o f oloctrons; change o f hardness duo to im p u rities depends on th e size o f th e foreign a to m re la tiv e to t h a t o f th e o th e r ato m s, whilo change o f eloctrical co n d u c tiv ity depends on th e periodicity o f th e oloctron m o tio n in tho foreign a to m relatiy c to t h a t in th e p uro atom .—J . S. G. T.
*The R atę of Diffusion in M etal Crystals an d A tom ie S tructure. W . S cith (Z. Elektrochem., 1935, 41, (12), 872-876).— Cf. M et. A bs., th is vol., p. 7. T he so lu b ility o f a m etal in solid lead a n d th e ra te o f diffusion o f th is m e ta l in tho lead are d ep en d en t on its place in th e periodic sy stem , a n d thereforo on th e ato m ie size a n d tlie n u m b er o f tho valcncy eleetrons.— J . H . W .
*The Effect of Crystal-Size on L attice D im ensions. G. I . F in c h a n d S. F ord- h am (Proc. P liys. Soc., 1930, 48, (264), S5-93).— I t is show n ex p erim en tally t h a t crystal-size can, a n d som otim es does, e x e rt an appreciable effect upon tho lattico dim ensions o f ionic cry stals.— J . S. G. T.
IV .— CORROSION
(Continued from p. 42.)
Action.of D ilute Acids on A lum inium . C harles F . Poe, R . M. W arnoek, a n d A. P . W yss (Itidust. and E ng. Clicm., 1935, 27, (12), 1505-1507).—T e sts were carriod o u t on sh e e t alum inium o f tlie com position : alum inium 99-20, iron 0-53, c o p p e r 0-03, Silicon 0-16% , a n d m anganese nil. Pieces o f th e sh eet w ere boiled in 0-liV acids for 30 m in u tes oaeh d a y fo r 12 w eeks a n d also allowed to s ta n d im m ersod a t 25° C. fo r v ary in g periods u p to 12 weeks. T h e resu lts
a r o ta b u la te d . T ests w ere also c a r r i o d o u t on Y a r i o u s alum inium ( i n c l u d i n g
dio-east) cooking utensils, th e eom positions o f w hich a re n o t given. O f tho inorganic acids, th e halogen acids secm to be m o st activo. O f tho organie acids, acotic a n d its chlorine derivatives, an d form ie a n d lactie, are ra th e r active.
Glycolic, hydridic, m alonic, oxalic, a n d su lp h u ro u s acids, am ong o thers, showod eonsiderablo a c tiv ity fo r tho iirs t few weeks, th e re a fte r decreasm g. M ost o f tho acids found in fru its a n d yegetables are more o r less ac tiv e on alum inium . I t is n o t know n to w h a t o x to n t tho so lu b ility o f alum inium w ould be a lte re d by th o o th e r co n stitu e n ts o f foods, n o r is i t suggosted t h a t alum inium is n o t a p ro p e r m ato rial fo r use in th e m an u factu re o f cooking utensils, th o physio- logical actio n o f its salts n o t being considered in th is article.—F . J .
tC orrosion-R esistance of A lum inium and Standard A lum inium -B asc Alloys.
P . Blabb (M etallurgia, 1936, 13, (76), 109-113).—T he corrosion-resistanee o f m an y alum inium alloys is reviow ed a n d t h a t o f alum inium a n d o f s ta n d a rd alum inium -base alloys including D u ralu m in , copper-silicon, c o p p e r-n ie k e l- silieon, alum inium -m anganese, a n d alu m in iu m -m ag n esiu m is com pared w ith special reference to th e influence o f im p u rities a n d alloying elem ents. P ra c ti- cal exam ples o f corrosion te s ts o f th ese alloys b y m eans o f th e salt-sp ray are given. A d d itio n al safeguards ag a in st corrosion, w here th o n a tu r a l p ro tectiv e film is in ad eq u a te, a re considered, a n d availablo m ethods o f p ro tectio n , e.g.
eleetrodeposited, p a in t, o r o th e r organie films, chem ical o x id atio n , a n d electro- ly tic o x id atio n are d e a lt w ith in brief.— J . W . D .
♦Additions of Inh ilń to rs to Solutions w hich Corrodo A lum inium . H an s R ohrig (Rev. M et., 1935, 32, (11), 577-580 ; also (sum m aries) L ight M etals Research, 1936, 4, (15), 241-2 4 3 ; a n d L ig h t M eials Rev., 1936, 2, (15), 257-259).— Seo M et. A bs., th is vol., p . 8.— H . S.
Corrosion of U nderground Cables. Ito P a n a ra (Elettrotecnica, 1935, 22, (18), 653-6 6 0 ; Sei. A b s., 1935, [B], 38,652).— P . discusses corrosion effects u n d e r tw o g ro u p s : (1) corrosion due to th e prescnce in th e soil o f e e rta in ehem icals a n d
1936
I V .— Corrosion 79
to irregularities in th e s h e a th ; an d (2) corrosion duo to s tra y eu rren ts in tho soil. P ro tectio n a g a in s t corrosion m a y be effected b y arm ouring tho cables, b u t carc has to bo ta k e n in th e selection o f th e m aterials. W here arm ouring is n o t possible, as fo r in stan ce in tow ns w here p la in lead-covcred cables aro draw n in to d u cts, th e u su a l p ractice is to arran g e fo r th o cablo-sheath to bo k ep t a t a p o te n tia l low er th a n th a t o f tho su rro u n d in g e a r t h ; in th is w ay no stra y eu rren ts leave tho cab le-sh eath ex cep t th ro u g h defm ite drainago points.
— S. G.
The Use o£ th e Schlum berger Circuit in th e Stuily of th e Electrolysis of Underground Pipew ork. R . G ib ra t (Rev. gen. filect., 1936, 39, (2), 51-69).—A detailed acco u n t is given of th o Schlum bcrgor difforential m eth o d fo r m easuring stra y eu rren ts betw een a n y p o in t in a buried cable a n d th e su rrounding soil, a n d tho p recau tio n s w hich m u s t bo ta k e n to onsuro accu rate resu lts aro discussed. M ethods o f p ro teetin g lead cable-sheath a g a in s t electrolytic corrosion aro survoyed.— J . C. C.
*The Influence of A dm ixtures on th e Corrosion of Z inc. A. I . Sam okiiotski and A. P . B liudov( VeslnikM etalloprom ishlennosli (Messenger M etal In d .), 1935, 15, (12), 122-124).— [In R u ssian .] T he so lu b ility o f zinc in 0-5% sulphuric acid is inereased b y a d d itio n s o f copper, iron, an tim o n y , arsenie, a n d tin an d decreased by cadm ium , alum inium , lead, a n d m ercury.—D . N . S.
'*The E lectrochem ical Anodic B ehaviour of Alloys. W . J . M uller (Z. EleJclro- chcm., 1935, 41, (11), 774-778).— R e a d before th e V erein D eu tseh er C hem ikcr E.V . (a fte r th o ex p erim en ts o f H . F reissler a n d E . P lettin g er). T ho e lec tro chem ical behaviour o f copper-zinc alloys containing from 29-3 to 89-0% copper w as in v cstig ated as reg ard s : (1) colorim etric d eterm in atio n o f th e anodic solubility an d th e ra tio in w hich th e com ponents go in to solution, (2) de te rm in a tion o f th e p o te n tia l ag a in st ap p ro x im ately n o rm al s a lt solution m ix tu res w hich correspond in com position to th o pro p o rtio n s o f tho solubility o f tho co n stitu en ts, (3) d e te rm in a tio n o f tho p a ssiv ity tim e o f th e alloys w hich, w ith tho abovc te sts, leads to conclusions as to th e prescnco o f a p ro te e tin g oxido layer.— J . H . W .
*Corro3ion of M etals by C ontact w ith L eather. R . F . In n c s (./. Internat.
Soc. Leather Trades Cliem., 1935, 19, (12), 5 4 8 -5 6 3 ; G. A bs., 1936, 30, 641).—
L cath ers ta n n e d w ith single ta n n in g m aterials (chrom ium , sy n ta n , su lp h itc cellulose, a n d 8 vegetahle tan n in s) w ere. k e p t in c o n ta c t w ith m e ta l strip s (steel, copper, zinc, tin , D u ralu m in , brass, a n d bronzc) for 36 w ecks a t relativ c hum idities o f 50, 70, a n d 90% a t room te m p e ra tu re , a n d a t 70% relativ c h u m id ity a t 37° C. Corrosion w as ju d g ed from app caran ce. O f th e m aterials tested , tin was tho m ost re s is ta n t a n d copper a n d its alloys wcrc th e least re s ista n t. O f th e Ieathers te s te d , t h a t ta n n e d w ith s y n ta n caused g re a te st corrosion, p ro b a b ly bccause o f a n a b n o rm ally low p u value, followed b y lcath ers ta n n e d w ith sum ac an d m yrobalans. L cath ers ta n n e d w ith oak b a rk , gam bier, m im osa, ąuebracho, a n d su lp h ite cellulose caused le a st co n o sio n . A p a rt from th e sy n ta n leath er th ere w as no d ire c t relatio n sh ip betw een le a th e r p n yalue a n d corrosion. T he a m o u n t o f corrosion inereased w ith inereasing te m p e ra tu re or hu m id ity . Corrosion w as inereased w hen leath ers w ere oiled w ith cod-liver oil co ntaining a b o u t 12% free f a tty acids, an d decrcascd b u t w as n o t elim inated w hen leath ers wero oiled w ith p e tro la tu m . (Cf. K u b ełk a, N em ec, a n d Z urav- lev (“ A ction o f vcgetablo ta n n e d le a th e r on m etallic iro n ” ), Oitir tcch., 1935, 24. 300-304).— S. G.
*A ttack by Liąuid Fuels on Certain M aterials. K . R . D ietrich an d W . L ohrengel (O d u . Kohle, 1936, 12, (5), 91-92).— R ecen t G erm an legislation dem ands th e ad d itio n o f 10% m eth an o l to e th y l alcohol in ten d ed for ad- m ix tu re w ith p etro l o r benzole. A n account is given o f com parative corrosion te sts, lastin g 10 weeks, on 12 lig h t alloys, p u re alum inium w ith an d w ith o u t M.B.Y. coating, o rd in ary iron, an d iron p ro tc c tc d b y coatings o f lead, tin , or
80 M etallurgical A bstracts
Vol. 3zinc. A ttn c k w as inappreciablo ex cep t in th o case o f p lain , galvanized, a n d lead-coated iro n , S ilum in w ith M.B.V. coating, a n d E lek tro n . Tho resu lts are sum m arized in com parative c u rre s.— P . M. 0 . R .
Corrosion in th e M inerał Oil Industry : Discussion. --- (O d u . Kohle, 1936,12, (5), 93-95).--- Baudrexel sta te d t h a t th o fuel ta n k s o f airc ra ft, w h eth er o f galvanized iron or lig h t m etal, w ere especially liable to corrosion owing to th e com bined effects o f a ir bubbles a n d m o istu re in tro d u ced during filling. H e recom m ended tho use o f sy n th etic lacą u er as a p ro tectiv e coating on account o f its high e lasticity . --- K la s distin g u ish ed betw een corrosivo effects as obseryed in open a n d closed system s, a n d reproduced graphically th e re su lts o f co m p arativ e te s ts on tin p la te , galvanized iron, an d sh eet iro n in 3 benzol m istu re s an d 3 o rd in ary p etro ls for periods o f 7-420 d ay s. --- Schikorr referred to com parativo te s ts on lig h t alloys.— P . M. C. R .
[Petroleum ] Eeflnery Corrosion. W . L. N elson (Petroleum Eng., 1936, 7, (4), 90-93).— T he prin cip al corrosive agents in refinery w ork are hydrogen sulpliide, hydroclilorie, sulphuric, a n d sulphurous acids, a n d am m onia. A ta b lo show s th e ty p e o f corrosion or otlier special form o f a tta c k to w hich tho various p a rts aro liable, a n d suggests some a lte m a tiv e m aterials. These include M onel a n d M untz m etal, alum inium -bronze, p u re alum inium , an d le a d : th o last-n am ed is m o st conveniently applied b y spraying, w hich process-is freq u en tly ad o p ted w ith copper an d copper-base alloys.— P . M. C. R .
Turlbine-Blade Erosion. C. R ic h a rd Soderberg (Electric J ., 1935, 32, (12), 533-536).—Erosion o f tu rb in o blading is aflected b y tho speed o f im p aet betw een blado a n d steam , th e a m o u n t o f m oisturo p a rtic ip a tin g in tho im p aet, an d tho p ro p ertie s o f th e blado m ateriał. T he existenco o f critical lim its of speed an d m oisture suggests t h a t a fte r a lim iting s tre n g th o f th e m ateriał ag a in st bom bard- m e n t b y w ater drops is exceeded, erosion is v ery rap id . B lades o f stainlcss Steel, p ro te c te d b y Stcllito shields silver-solderod to tho blades, havo given tho m o st prom ising resu lts. C hrom ium -plated blades liave good in itia l resistance, b u t th o coating is Kable to crack, a fte r w hich erosion is rap id . A n erosion testin g m achino, in w hich a specim en is ro ta te d a t 12,000 ft./seco n d , strik in g a J-in. jc t o f w ater a t each revolution, is briefly described.— J . C. C.
V.— PROTECTIO N (O th cr th a n E lectrodeposition.)
(Continued from p. 43.)
*Oxide Films on A lum inium and Its Alloys. A. G. C. G w yer an d N . D. P ullen (Rev. M U ., 1935, 32, (12), 658-667).— A generał discussion o f th o su b ject o f anodic films on alum inium is followed b y a n account o f investigations o f films produced in chrom ic acid, oxalic acid, an d sulphuric acid on alum inium alloys containing copper 3-12, zinc 13, or Silicon 10-12% . T he thickness of tho films a n d tho effect o f th e tre a tm e n t on th e u nderlying m e ta l w ere stu d ie d m icro- scopically, a n d num erous photom icrographs are given.— H . S.
The Anodic Oxidation of A lum inium w ith P articular Reference to the B ritish P atents. --- (B rit. A lu m in iu m Intelligence M em orandum l D / l a 3 6 ; a n d (sum m ary) Light M etals Research, 1936, 4, (13), 203-206).— R eference is mado to th e facto rs w hich influence tho n a tu ro o f tho film produced b y anodic oxida- tio n , a n d to m ethods o f m odifying its p ro p erties b y su b seąu en t tre a tm e n ts.
T h e ch aracteristics o f oxide films, an d th e ir applications in service, aro d is
cussed.— J . C. C.
On the Surface Protection of A lum inium an d A lum inium Alloys. W . B ire tt (M aschinenbau, 1935, 14, (21/22), 615-618).— V arious m ethods fo r producing oxide films on alum inium are discussed.— K . S.
1936
V I .— Electrodeposition 81
*Surface T reatm ent by W elding Techniąue [Metal Spraying] for the Production o£ Coatings. A. M attin g (M aschinenbau, 1935, 14, (23/24), 683-686).—The tcchniąuo o f m e ta l sp ray in g is deseribed a n d th o p ro p erties o f sp ray ed coatings aro exam ined. I t is concluded t h a t such coatings have n o t tho s tre n g th nor the w ear-resistance o f tho solid m etal owing to th o ir non-hom ogeneity. Consc- ąu en tly th e use o f such coatings m u s t be re stric te d to special purposes, such as th e covering-up o f pores, &c., th e p ro d u ctio n o f alum inium coatings, o r tho beautifying o f m e ta l o r o th e r surfaccs.—K . S.
Painting A lum inium and Its Alloys. Ju n iu s D . E d w ard s an d R o b e rt I.
W ray (In d u st. and Eng. Chem., 1935, 27, (10), 1145-1146).—M inor diflerences in p a in t adhesion h av e been n o ted on d ifiere n t w ro u g h t alloys o f alum inium , and some observations on th e correlation o f p a in t adhesion a n d alloy com- position are presented. A n im p o rta n t facto r discusscd, w hich resu lts in loss of p a in t adhesion, is cliem ical reactio n a t tho interface betw een p a in t film and m etal. Good resistance o f th o vehicle to alkali is generally found in practico to help p a in t adhesion. W hen th e a lk a lin ity is due to m agnesium , i t is related to its stru c tu ra l occurrenco a n d d is trib u tio n ra tlie r th a n to th e am o u n t p resent.
Combined as Mg2Si or as M gZn,, i t is moro reactiv e th a n w hen in solid solution.
Tho p roduction o f passive surfaces, as b e st exem plified b y c ertain anodic c o a t
ings, m inim izes a n y diflerences betw een alloys a n d gives a n excellent base for holding p a in t, p a rtic u la rly w here subjected to im m ersion in w ater o r v e ry lium id conditions. E v en w ith o u t special surface p rep aratio n , alum inium alloys liold p a in t v ery satisfacto rily in com parison w ith o th e r s tru c tu r a l m etals. I n th e pain tin g or rep ain tin g o f surfaccs w hich liave been corroded, prełim inary tre a tm e n t w ith ch ro m ate solution h as been found eflective.— F . J .
Painting Z inc and Z inc Alloy Surfaces. H arley A. N elson (In d u st. and Eng.
Chem., 1935, 27, (10), 1149-1151).— Tho fa c to rs th o u g h t to influence tho in itial adherence a n d adherence re te n tio n o f p a in t on zinc a n d zinc alloy s u r faces aro discusscd. These are eonsidered in th e lig h t o f surface relationships th a t m ay e x ist betw een th e m e ta l a n d tho p a in t a n d tho possible influence o f changes in th e cliem ical a n d p h y sical n a tu rę o f th e p a in t film on ageing. A lim ited th eo retical discussion is given o f (1) selective a b s o rp tio n ; (2) progressiye changes in th e p a in t film ; (3) d istu rb a n c e o f th e oxide film norm ally existing a t t h e surfaces o f th e m e ta l; a n d (4) electrolytic a tta c k o f th e m etal. P re- tre a tm e n t o f tho m e ta l surface before p ain tin g is also discusscd. T he pigm ent th a t h as th e m o st bcneficial eflect on adherence re te n tio n , p a rtic u la rly o f air- drying oil prim ers, in w hich acid decom position p ro d u cts are form ed, is m etallic zinc pow der (zinc d u st).—F . J .
VI.—ELECTRODEPOSITION
(Continucd from pp. 43—15.)
Electrodeposition of Chrom ium fo r W ear Resistance. J o h n K ro n sb ein (./.
Eleclrodepositors' Tech. Soc., 1936,11, 2 3 -2 6 ; a n d (ab stract) M ci. In d . (L o n d .), 1936, 48, (6), 193-194).—P łu g gauges are co ated w ith 0-007-0 012 in. of chrom ium o f w hich 0-002-0-004 in. is gro u n d off to se t u p th e gauge.
Tlie base m etal should bo liardened before p latin g to o b v iate sub seq u en t chipping. T he electrolyte consists o f chrom ie acid 250 g rm ./litre a n d sul- phuric acid 2-40 g rm ./litro , a n d is used a t 37°-41° C. an d 80-200 a m p ./ft.2.
C urrent consum ption is 500 a m p .-h rs./ft.2 for 0-001 in. Throw ing pow er is poor, a n d anodes should conform to th e cathode sliape. T he su lp h a te ra tio should bo m ain tain ed betw een 60 a n d 100. C hrom ium inereases th e life o f gauges fro m 10 to 25 tim es as com pared w ith h ard en ed steol, b u t is useless for cu ttin g edges.— A. I. W .-W .
The Electrodeposition of Bronze Using Bronze Anodes. S. B aier an d D. J . M acnaughtan (J . Eleclrodepositors' Tech. Soc., 1936,11, 1 -1 4 ; also Tech. Publ.
Internat. T in Res. Develop. Couneil, Series A , 1936, (27), 14 p p . ; a n d M et. In d .
8 2
Metallurgical Abstracts
Vol. 3(Lond.), 1935, 47, 543-544, 567-570; diseussion, 1936, 48, 15-18).— Satis- fa c to ry deposits o f bronzo, can be o b tain ed from a n electrolyte containing copper cyanido 150 g r m ./ l i t r e , sodium sta n n a te , 50 g rm ./litre , a n d sodium cyanidc, 15 g rm ./litre a t 65° C. a n d c u rre n t densities u p to 50 a m p ./ft.2. Tho p n o f th e solution w as m ain tain ed by caustic soda a t 12-5-12-7 an d controllcd by th e use o f alizarin yellow as a colorim etric in d icato r in sam ples o f electrolyte d ilu te d 100/1. A nnealcd c a st bronzo anodes containcd 12% tin . A nodę an d cathode efficiencies in relatio n to c u rre n t d en sity , althougli d isco rd an t, allow th e m e ta l co n te n t of tho electrolytc to bo controllcd durin g operation. Bronzo deposits o f m ore th a n 0-0003 in. thickness aro com pletely non-porous, an d throw ing pow er is cxccptionally high. A bronzo deposit o f 0-0002 in. is a satisfacto ry u n d crco at for chrom ium . T he hard n ess o f th e deposit inereases w ith tho tin co n te n t from B rinell N o. 222 a t 11-7% tin to 345 a t 17-0% tin . M ethods o f an aly sis o f tho electrolytc a n d deposits are described.— A. I . W .-W .
The Electrodeposition of Bronze Using Bi-M etallic Anodes. C. B ćchard (./.
FAcctrodepositors' Tech. Soc., 1930, 11, 15 -2 2 ; a n d Tech. Publ. Internat. T in Hes. Dcvdop. Council, Series A , 1936, (28), 8 p p.).— B ronze can be deposited from solutions o f am m onium stan n o -o x alate a n d am m onium cupri-oxalate in th e presence o f oxalic acid. Insoluble anodes are u sed,.and tho coppor an d tin co n tcn ts o f tho electrolytc is m ain tain ed b y tw o independent au x iliary circuits w ith cathodes cnclosed in porous po ts. Increase in c u rre n t d en sity o r decreaso in tem p eratu ro fav o u r th e deposition o f tin . The electrolyte is u n stab le, tho tin being oxidized to stan n ic s a lt b y th e ca ta ly tic action o f tho copper sa lt. A solution containing potassium cuprocyanide, stan n ic ehloride, potassium liydr- oxidc, an d potassium cyanido will give bronze deposits having a tin co n ten t v ary in g from 10 to 25% according to th e pro p o rtio n s o f th e eo n stitu en ts.
Copper an d ti n an d insoluble anodes are u sed w ith in d ep en d en t co n tro l o f c u rre n t d en sity to m a in ta in tho balanee o f anodo a n d cathode cfticiency.
[Note : Tho tw o circu it diagram s are reverscd.]—A. I . W .-W .
Progress o£ Nickel in the P a st Ten Years. J o h n F . Thom pson (Itev. MLI., 1935, 32, (11), 509-516).— T . surveys th e progress in tho ex tractio n o f nickel, a n d o f nickel alloys a n d nickel steels durin g th e p a s t 10 years, in w hich tho w orld’s consum ption o f nickel h as doubled, a n d m entions adyanccs in elcctro- deposition o f nickel.— H . S.
tT h e Present Position o£ Nickel and Chromium Deposition. M. B allay (Rev.
M et., 1935, 32, (10), 494-500).—A reviow o f recen t advances.— H . S.
Platinum Plating. T aro Y oshida (Japan Nickel Rev., 1936,4, (1), 82-84).—
[In E nglish a n d Jap an ese.] A solution containing p latin u m chlorido 0-5, caustic soda 0-25, sodium ph o sp h ate 6 00, sodium bicarbonate TOO, potassium n itra to TOO, boracic acid 1-2 oz., a n d w a te r 1 gali. is reeom m ended. A n a lte m a tiv o solution contains am m onium potassium cliloride 15-5, am m onium ehloride 6-25, sodium c itra te 125-00 grm ., a n d w a te r 1 litre. A p latin u m plato is used as anodę. A ro lta g e o f 5 -6 v. is necessary. Tim e o f p latin g depends on th e n a tu rę o f th o base m etal.—W . A. C. N .
Methods of P latinum P lating. K inzo S a d a k a ta (J a p a n N ickel Rev., 1936, 4, (1), 85-93).— [In E nglish a n d Jap an ese.] F o r econom ic reasons carbon anodes aro w idcly used. B rusli p latin g is freq u en tly adopted. T he following solutions are m entioned as being in generał use : (1) P la tin u m (as p latin u m cliloride) 5 grm ., am m onium ph o sp h ate 45 grm ., a n d sodium p h o sp h ate 240 grm ., w ater 1 litre. Boil u n til am m onia fum es are rem oved a n d tho solution is slightly acid. U se w arm . (2) P la tin u m (as p la tin u m ehloride) 4 grm ., am m onium ph o sp h ate 45 grm ., boric acid 15 grm ., w a te r 1 litre . U se a t 70°-80° C. w ith a eu rre n t d en sity of 0-1 am p ./d m .2. (3) P la tin u m am m onium ehloride 15 grm ., caustie soda optim um , am m onium ehloride 5 grm ., citric acid 100 grm ., w a te r 1 litre. U se a t 80° C. E .m .f. 5 -6 v . (4) H ydrochloroplatinic acid 7 grm ., am m onium p h o sp h ate 27 grm ., sodium p h o sp h ate 140 grm ., sa lt
