METALLURGICAL ABSTRACTS
(G E N E R A L A N D N O N -F E R R O U S )
Yolume 3 JANUARY 1936 Part 1
I — P R O P E R T IE S O F M ETALS
♦Diam agnetism of Copper. S. R a m a c h a n d ra R ao (Proc. In d ia n Acad. S ci., 1935, 2, (3A), 249-259).— Colloidał copper, p rep arcd by clcctrical dispersion in benzene or p ro p y l aleohol, is found to liave a diam agnetie su sccp tib ility (y) w hich increases as th e size o f tho particles decreases, th e critical diam eter of th e partieles below w hich largo ehangcs o f y occur being 0-8 y.. T he value o f y for copper in bu lk is 0-080. Tlić re s u lts w ith colloidał pow ders cnablo 7 for tho surface lay o r a n d th e tliickness o f th is lay er to be d eten n in ed . These are, respectively, 0-200 an d 300 A. On th e basis o f th e th e o ry due to H o n d a an d Shim izu, tho d en sity o f th e surface lay er is found to be 8-404; tho d e n sity of th e m etal in m ass is 8-943.—J . S. G. T.
*Experim ents on the Electrolytic Separation of the Isotopes o£ L ithium . A.
E ueken a n d K . B ratzler (Z. p hysikal. Chem., 1935, [A], 174, 2G9-272).—
A tte m p ts to soparate lith iu m in to its isotopes b y electrolysis o f lith iu m su lp h ate solution using a flowing m ercury cathodo failed to eS ect a n y appreciable separation a fte r fo u r rep etitio n s.— B. BI.
*On the M agnetostrietion o£ Single Crystals o£ Niekel a t Various Tem peratures.
K o ta ro H onda, H a k a r M asum oto, a n d Y u k i S hirakaw a (Sci. Rep. Tóholcu Im/p.
U niv., 1935, [i], 24, 391-410).— [In E nglish.] T he m ag n etizatio n o f single cry stals o f niekel a t yario u s tem p eratu res ranging from — 252° to 370° C. was m easured b y the ballistic m ethod. T he m ag n etizatio n a t o rd in ary te m p e ra tu res in th e direction o f th e [ 111] ax is increases a t first rap id ly a n d th e n slowly w ith th e inerease o f tho field, a n d a fterw ard s reaches a sa tu ra tio n valuc. As th e tem p e ra tu re is inereased, tho m ag n etizatio n in w eak fields g rad u ally bocomes easior a n d th e sa tu ra tio n value o f m ag n etizatio n becomes less. The m agnetization curvcs in th e direction o f th e [110] a n d [ 100] axes a re sim ilar in fo rm ; th e y are alm o st tlie sam e as for th o [111] axis, b u t a t Iow tem p eratu res th e sa tu ra tio n valuo is n o t reached even in a field o f 1000 oersteds. Tho sa tu ra tio n value o f m ag n etizatio n o f a niekel c ry s ta l a t absolute zero h as bcen estim a te d to be 523 gauss.—S. G.
*Ionization of H ydrogen Gas in Contact w ith Platinum , Copper, and Niekel.
C. Y. Meng, P a u l A. A nderson, a n d Y . M. H sieh (./. Chinese Chem. Soc., 1935, 3, 103-114).— [I n E nglish.] Tho ionization o f hydrogen in c o n ta c t w ith p latin u m , copper, an d niekel is stu d ied q u a n tita tiv e ly a t different te m p e ra tures. A n illu stra te d description is given o f th o ionization eham ber a n d tho purifier em ployed. M ercury v ap o u r w as elim inated b y m eans o f a potassium tra p . Io n izatio n o f hydrogen oceurred in th e caso o f all th re e m etals, tho e u rre n t observed being very sm ali a t room te m p e ra tu re an d inereasing m arkedly a t a b o u t 05° C. Copper a n d niekel produeed a slightly highor dogree o f ionization th a n p la tin u m : th o au th o rs deduee t h a t th e a ctiv atio n o f hydrogen in c o n tac t w ith p latin u m , w hich does n o t occur if copper or niekel are used, can n o t be th e re s u lt o f ionization.—P . M. C. R .
The Effect of Crystalline Fields on the M agnetic Susceptibilities of Sm + + + a n d E u +++ and the H eat Capacity of Sm + + +. A m elia F ra n k (Phys. Bcv., 1935, [ii], 48, 765-771).— B y assum ing th a t th e io n is su b ject to a crystaU ine field of a special ty p e , i t is show n t h a t th eo retical yalues o f th e p aram ag n etio suscepti- b ility ofsam arium (Sm + + + ) are in satisfacto ry ag reem en t w ith th e experim ental
* Denotes a paper describing the results of original researoh.
f Denotes a lirst-class critical reviow.
B
Metallurgical A bstrads
Vo l. 3d a ta o f F reed over th e rangę from 74° K . to room tem p eratu ro . I n c o n tra st to Sm + + +, europium ( E u + + + ) behaves lik e th e free ion even in th e presence o f a cry stallin e field. T he generał shape o f th e b e a t e a p a c ity -te m p e ra tu re curye o fS m + + + is sliówn to agree w ith t h a t o b tain ed experim entally b y x\hlberg an d F reed , b u t th e theoretical yalues o f h e a t eap aeity are eonsistently low er th a n th e ex p erim en tal values.—J . S. G. T.
* 0 n the Increase in D eform ability and Decrease in Cleavability [of Tin, Bism uth, and Zinc] w ith Increase in Tem perature. G. T am m an n a n d W . M uller (Z. M etallkunde, 1935, 27, 187-189).—I f single cry stals o f th e aboye m etals are in d en ted w ith th e B rinell bali, ch aracteristic tw in lamellas ap p ear in definite erystallographie directions around th e im pression. Somewhafc sim ilar effects are produced b y scratching th e surface o f th e e ry s ta l w ith a diam ond, sm ali p arallel fissures being produced on eith er side o f th e scratch form ing a lierring- bone eileot. W ith increasing tem p eratu re o f te s t these effects become gradu- ally less pronounced a n d eyen tu ally disappear, i.e. th e once b rittle m etal becomes p lastic. T h is disappearance tak es place a t definite t-em peratures w hich correspond w ith those a t w hich th e m e ta l can bo w orked, i.e. for zinc 130° C., for b ism u th 150° C., a n d for an tim o n y 300° C. Single cry stals of b ism u th can be benfc w itb o u t fractu re a t tem p eratu res above 100° C., w hereas those o f an tim o n y can be b e n t only above 350° C. Since an tim o n y a t 300° C.
is ap p ro x im ately as b rittle as b ism uth a t 20° C. i t follows t h a t th e tw o m etals are cąually b rittle a t tem p eratu res w hich are th e sam e fractio n o f th e ir m elting p o in ts in ° abs.—A. R . P .
♦Effects of H igh Shearing Stress Combined w ith H igh H ydrostatic Pressure.
P . W . B ridgm an (Phys. liev., 1935, [ii], 48, 825-847).—Mean h y d ro static pressures u p to 50,000 k g ./cm .2 com bined w ith shearing stresses u p to th e p lastic flow p o in t are produced in th in discs confined betw een hardened Steel p a rts so m ounted t h a t th ey m ay be subjected to norm al pressure an d to rq u e sim ultaneously. Q ualitative an d q u a n tita tiv e studies are m ade o f th e effects o f such stresses. Am ong th e q u a lita tiv e effects, i t is found t h a t m any sub- stances, e.g. celluloid, norm ally stab le become u n stab le a n d m ay d eto n ate, an d som e substances norm ally in e rt to each oth er, com bine explosively. The shearing stress a t p lastic flow a t 50,000 k g ./cm .2 m ay increase to as m uch as 10 or more tim es its norm al value a t a tm . p re s su re ; th is is co n tra ry to accepted views w ithin a narro w cr pressure rango. I f th e substance undergoes a poly- m orphic tra n sitio n u n d er these conditions o f stress, a b reak m ay occur in th e shearing stress-pressuro curye. A n u m b cr o f new polym orphic tran sitio n s has th u s been found am ongst th e elem ents, o f w hich 57 h ave bcen exam ined. T he m etals exhibiting polym orphism are lith iu m , stro n tiu m , calcium , barium , cadm ium , zinc, yanadium , m anganese, an tim o n y , tellurium , lan th an u m , cerium , erbium , th alliu m , bism u th , th o riu m , tin , y ttriu m , a n d praseodym ium .
- J . S. G. T .
*Polym orphism, Principally of the Elem ents, up to 50,000 kg./cm .2. P . W . B ridgm an (Phys. Jłev., 1935, [ii], 48, 893-906).—A new tech n iąu e, w liereby pressures o f 50,000 k g ./cm .2 an d liigher can be applied to solids, a n d para- m eters o f a n y tran sitio n s m easured, is described. M any o f th e elem ents hayo been exam ined, in th e new pressure rangę, for eyidence o f polym orphism . N ew m odifications are found in tlie cases o f bism u th , m ercury, th alliu m , tellu riu m , gallium , a n d iodine.—J . S. G. T.
*The Theory of Surface Tension of Liquid Metals. D . V. G ogate a n d D ulek S in h a ICothari (Phil. M ag., 1935, [vii], 20, 1136-1144).—A form uła for th e surface tension o f liąu id m etals is deriyed by m eans o f a th eo ry w hich applies F e rm i-D ira c sta tistic s to th e m otion o f clectrons in a piane m onom olecular film. S atisfaeto ry agreem ent betw een ealculated a n d ex p erim en tal yalues o f surface tension is show n b y resu lts relatin g to 15 m etals.— J . S. G. T.
*The Pressure Effect of E lectrical R esistance of M etals. N . K . S ah a (In d ia n J . Pliysics, 1935, 9, (6), 623-635).—T he pressure coeif. o f electrical resistance of m etals a n d th e chango o f resistance a t diflerent pressures aro calculated using th e rigid ionie m odel o f N ordheim . Good agreem ent is found betw een experim ental a n d th eo retical values in th e cases o f gold, silver, an d copper, an d , in generał, for m etals o f Iow com pressibility. T he resu lts are eom pared w ith those o f K ro ll using F e rm i’s s ta tistic a l th eo ry o f ionie p o ten tial. N ordheim ’s model, using a screened Coulom bian p o te n tia l, gives th e m ore co n sisten t results. The alkalis, possessing y ery high com pressibility, yield no satisfacto ry resu lts on eith er form o f th eo ry .— J . S. G. T.
tSuperconduetivity. H . G. S m ith a n d J . O. W ilhelm (liev. M odern Physics, 1935, 7, 237-271).—S u p erco n d u etiy ity is com prehensively reviewcd. T he subjects discussed inelude : th e phenom enon o f su p c rc o n d u c tiv ity ; super- conducting m e ta ls ; in te rru p tio n o f su p erco n d u ctiv ity b y a m agnetic field;
d istrib u tio n o f m agnetic field aro u n d a su p e rc o n d u c to r; cu rre n t in a closed supereonducting c irc u it; therm oelectrio effects; specifio h e a ts ; th e rm a l c o n d u c tiv ity ; su p erco n d u ctiv ity in th in film s; anom alous supereonducting alloys; theories o f su p e rc o n d u c tiv ity ; th erm o d y n a m ic s; elec tro d y n am ics;
the London th e o ry ; th e spontaneous c u rre n t th e o ry ; ąu an tu m -m e c h a n ic a l theories.—J . S. G. T.
fT he State of R esearch on Superconduetiyity. W . M eissner ( Elektrotech. Z ., 1935, 56, 1061-1065).-—R esearches m ade during recen t years have led to th e following conclusions : su p erco n d u etiy ity oeeurs n o t only in pu re m etals b u t also in all ty p e s o f alloys including in term etallie eom pounds. T he tra n sitio n p o in t to su p ereo n d u ctiv ity varies betw een 0-3° an d 9-2° abs. a n d is influenced by te m p e ra tu re a n d by e x tern al m agnetic field s; in b o th cases hysteresis efieets have been observed an d in m assive specim ens o f pu re m etals th e m agnetic induction su ddenly becomes zero a t th e tra n sitio n p o in t. Tho specifio h e a t a n d th e h e a t co n d u etiv ity cliange only slightly, b u t th ere is a relation b e tw een th e effect o f m agnetic fields a n d th e change in specific h eat. Theories o f su p erco n d u ctiv ity are briefly discussed.—B . BI.
1936 I I . — P r o p e r t i e s o f A l l o y s 3
I I .— P R O P E R T IE S OF ALLOYS
_ *The System Iron-C obalt-C obalt Silieide-Iron Silicide. R u d o lf Vogel an d K u r t R o sen th al (A rch . E isen h iitten w esen , 1935-1936, 9, 293-298).—T he system w as exam ined b y th e rm a l a n d m icrograpliie m ethods an d th e e ąu ilib ria are shown in a series o f te r n a ry a n d ąu asi-b in a ry diagram s. CoSi a n d FeSi form a continuous series o f solid solutions, a n d on ad d itio n o f th e o th e r m e ta l form th e te r n a ry com pound FeCoSi below 980° C. I n th o seetion iro n -co b alt-C o 2S i- FeC oSi-FeSi th ere are fo u r planes o f 4-phase eąuilibrium , tw o o f w hich relate to tran sfo rm atio n reactions, tw o to eu tectic reactions, a n d one to a eutectoidal transform ation. Analogous planes o f e ąu ilib ria occur in th e seetion F e S i- FeCoSi-Co2Si-CoSi, a n d sińce FeS i a n d CoSi a n d CojSi a n d FeCoSi form continuous series o f solid solutions th e 3-phase e ąu ilib ria in th e ąu asi-b in ary system Co2Si-CoSi m erge in to those o f th e ąu asi-b in a ry sy stem FeSi-FeCoSi.
—A. R . P .
*The Reflectiou Coefficient of the Series of Copper-Nickel Binary Solid Solu
tions. P . B ergm ann an d W . G uertler (Z. tech. P h ysik, 1935, 16, 235-236).—
R eflection eoeffs. o f 9 eopper-nickel alloys co ntaining from 0 to 100% o f nickel are ta b u la te d for th e rango o f w ave-iengths 4670-6100 A. T he se!ectivo refleetivity o f copper te n d s to d isap p ear as th e % o f nickel in tho alloy is inereased. A lloys containing a b o u t 25 ato m ie-% o f nickel o r m ore, have a b o u t th e sam e reflectiyity as p u re nickel.—J . S. G. T.
4 Metallurgical. A bstrads
Vo l. 3*Tke System Copper-N ickel-Iron. W . K o ste r an d W . D annólil (Z. Melall- lcunde, 1935, 27, 220-226).—The te rn a ry diag ram a n d several pscudo-binary seetions th ro u g h i t liave been constructcd from th e resu lts o f th e rm a l analysis, m agnetom etrie m easurem ents, an d d eterm inations o f th e electrieal resistanee.
T he bou n d ary o f th e field in w hich th e a - y tran sfo rm atio n oeeurs is a stra ig h t lino joining th e copper corner o f th e te rn a ry d iag ram w ith 28% niekel on th e iro n -n iek e l side. T he miseibilifcy gap in th e iro n -eo p p er sy stem is grad u ally closed b y ad d itio n o f niekel, disappearing en tirely w ith 27% niekel a t 1220° C.
a n d w ith 82% niekel a t room te m p e ra tu ro ; henee alloys w ith in tliis rango aro am enablc to precipitation-hardening tre a tm e n t, w hich in ee rta in alloys con- ta in in g a b o u t 50% niekel leads also to changes in th e Curie p o in t.— A. R . P .
tO n the M echanism of Precipitation [in Supersaturated Solid Solution Silver- Copper Alloys]. U . D ehlingcr [Z. M etallkunde, 1935, 27, 209-212).—Miero- seopie observations on th e sep aratio n o f silver fro m su p e rsa tu ra te d solid solution in copper shows t h a t th e p articles o f silver first pre c ip ita te d in no w ay influence th e ra to or form o f sub scq u en t preeip itatio n s, a n d therefore p re c ip ita tio n can n o t bo a ttrib u te d to nuelei fo rm atio n b u t m u s t bo ascribed to lattieo d isto rtio n p robably a t th e boundaries o f mosaie bloeks. A t these p oints very th iii film s o f silver are p robably first form ed, a n d th esc su b seąu en tly eoagulato in to grains w hich ean be detectod first by X -ray s an d th e n , as th e y grow in size, by mieroscopie exam ination. I n deform ed a n d recrj'stallized m etal m icro- scopie observations reveal th e presence, a t th e boundaries o f regions in w hich p recip itatio n has a lread y begun, o f a n aetive faeto r whioh accelerates fu rth e r p recip itatio n an d w hich is th e cause o f th e high ra te o f p recip itatio n , a n d th e p ro d u etio n o f m icroseopically deteetable heterogeneity.—A. R . P .
Caro Bronze. --- (M achines, 1935, (N ov.), 6).— A b rie f descrip tio n is given o f a phosphor-bronzo bearing alloy eontaining copper 91-2, ti n 8-5, an d phosphorus 0 -3 % ; th e alloy is used in th e cold-draw n eondition.— P . M. C. R .
♦The Materials for Condenser Tubes. Y oshiro F u jii (Tetsu-to-Hagana (J.
Iron Steel In st. Japan), 1935, 21, 568-575; G. A bs., 1935, 29, 7912).— [In Jap an ese.] Sevon k inds o f eopper-basc alloys a n d tw o stainless stcels wore subjeeted to te s ts o f sp. gr., eorrosion in a 3 % acjueous sodium ehloride solu
tion, corrosion in sea-w ater, th erm al co n d u ctiv ity , m icro stru etu re, a n d various m echanical properties. T he a e tu a l te s t o f th e sm ali eondensers w hich were specially constructcd using tu b es m ado o f tho abovc-m entioned m aterials w as carried o u t over a period o f 4 y ears. I n a ll thesc te s ts th e following alloys show ed good resu lts : H iro-ken (The H iro N a v a l Arsenał) A a llo y ; alum inium 3, zinc 16% , rem ainder c o p p er; a n d zine 27, tin 1, iron 0-03% , rem ain d er copper.—S. G.
*M agnesium -A lum inium -N ickcl Alloys. G. G uzzoni (Chimica e induslria (Ita ly ), 1935, 17, 293-300; a n d In d u slria mcccanica, 1935, 13, 690-696; C.
A bs., 1935, 29, 7917).—T h e effect o f ad d itio n s o f niekel to alloys o f m agnesium a n d alum inium w as doterm ined. Tho b e st re su lts w ere o b tain ed w ith 3-5- 4-0% alum inium an d 0 ’5-0-6% niekel. A ll th e alloys reąu ire a flux to im prove c a s ta b ility ; a m ixturo o f anhy d ro u s m agnesium ehloride an d sodium ehloride in eąu al p a rts w as found best. Increasing th e niekel e o n te n t above 0-5%
im proves th e tensile stre n g th slightly, b u t reduces th e ca sta b ility an d d u c tility . Alloys eontaining more th a n 2 % niekel are alm o st inipossiblo to m ake owing to th e lim ited solubility w ith alum inium p resen t, even thougli m agnesium an d niekel alone m ix in all proportions. T he optim um alloy m entioned above has th e following properties : tensile stre n g th 17—19 k g ./m m .2, elongation 8 -1 2 % , B rinell hardness 50-55. T he b est conditions for pouring are to h e a t to 850° C., liold for 10-15 m inutes, an d to p our w hen tho te m p e ra tu re h a s deereased to 760°-780° C. E x tru sio n is carried o u t as for o th er lig h t alloys, a tem p eratu re o f 300°-350° C. bcing best. A tu n g ste n -ste e l die should be used, tem pered a t 450° C .; m oulds are b est m adę o f iron o r m ild steel free from g rap h itc an d
1936
I I .— Properties of A lloys
nickel. Tliese alloys could n o t bo h e a t-trc a tc d , liardencd, tem pered, or annealed successfully. F o r cx tru sio n s th e alloy giving tho b e st rcsu lts con- taincd alum inium 7 an d nickel 1-0% ; i t had a tensile s trc n g th o f 30-31 k g ./
m m .2 an d a n elongation o f 14% . N ickel m akcs th o alloy m orę corrosive, th u s countcracting th e im provcm ent due to alum inium . Tho alloys are difficult to weld.—S. G.
*The Eąuilibria Between Iro n and Nickel and Their Silica-Saturated Silicates.
P e te r B ardenheuer a n d E rw in B rau n s (M ilt. K .W . In s i. Eisenforschitng, 1935, 17, 128-132).—T he e ąu ilib ria betw een n ickel-iron alloys a n d nickel-iron silicate slags a t 1600° C. w ere d e te rm in e d ; th o d istrib u tio n o f iron an d nickel betw een m etal a n d slag lay ers agrees v cry closely w ith tho ideał m ass- action law. Tho oxido c o n te n t o f th e m etal lay er in nickcl-rich m elts is d e te r
m ined alm ost en tirely b y th e nickel oxide co n te n t o f tho slag la y e r a n d decroases w ith deereasing te m p e ra tu ro ; a d d itio n o f excess o f iro n to th o m etal lay er changes th e p a rtitio n coefE. o f nickel oxide only b y a b o u t 5 % .—A. R . P.
Magnetic Properties of Some Nickel Alloys. R a y C haudri an d P . N . Sen G u p ta (Science and Cullure, 1935, 1, 114-115; C. Ab-s., 1935, 29, 7918).—
50 :5 0 and, GO : 40 alloys o f nickel an d alum inium resem ble nickel oxido in m agnetic su scep tib ilities; hysteresis is ab sen t. I t is n o t possible to locate tho Curie po in t. A 70 : 30 alloy o f nickel a n d clirom ium shows a chango o f cu rv atu re on th e tem p eratu re-m n g n etic su scep tib ility diagram a t a b o u t 400° C.— S . G.
*The Solubility of D euterium and Hydrogen in Solid Palladium . A. S ieverts an d G. Z ap f (Z. physilcal. Chem., 1935, [A], 174, 359-364).-—T he values ob- tain ed betw een 300° an d 1100° C. aro in ap p ro x im ate agreem ent w ith those o btained b y o thers. T he re la tio n betw een th e solubilities o f deuterium an d hydrogen is 0-07 a t 300° C., 0-91 a t 1000° C., an d ap p ro x im atcs to u n ity a t higher te m p eratu res. Tho solubility o f b o th isotopes in p alladium is pro- portio n al to tho squarc ro o t o f th e gas pressure a t c o n sta n t tem peraturo.
— B. BI.
*The Electrical Resistance of H ydrogen-Charged W ires of Palladium -Silver and Palladium -G old Alloys. A. S icverts a n d H . H agen (Z. physikal, Chem., 1935, [A], 174, 247-261).—T he p ressu re-co n ccn tratio n isotherm s o f alloys w ith 5 a n d 10% silver are sim ilar to those o f p u re p a lla d iu m ; th e y show- hysteresis a t 150° a n d a t 200° C., a second section in w hich th e concentration o f hydrogen is in d ep en d e n t o f th e pressure. All o th e r isotherm s h ave a p ara- bolio shape. Tho pressure-eleotrical resistance isotherm s are sim ilar to those o f palladium u p to 30 ato m ic-% silver, b u t tho change in resistance for equal inerem ents o f pressure an d hydrogen c o n te n t becomo sm aller w ith inereasing silver co n ten t. In alloys w ith 30 a n d 40 ato m ie-% silver th e electrical resistance becomes sm aller b y ab so rp tio n o f hydrogen w ith in a definite rango o f tem p eratu ro an d p re s su re ; in alloys w ith 50 a n d 00 ato m ic-% silver a b so rp tio n o f hydrogen again causes largo inereases in tho resistance. P a lla d iu m - gold alloys behave sim ilarly to pallad iu m -silv er alloys w ith th e sam e atom ic-%
palladium , b u t th e decreaso in resistance b y hydrogen ab so rp tio n in tho 35 atom ic-% gold alloy is m uch g reater th a n in th e 39 atom ic-% silver alloy.
— B . BI.
*On the E ąuilibrium D iagram of the Silver-Rich Silver-A lum inium Alloys, w ith a Note on the N aturę of the Transform ations. Ic h iji O b in ata a n d M asam i H ag iy a (K in zo ku no K e n b ju , 1935, 12, 419-429).— [In Jap an ese.] Tho eąuilibrium diagram o f th e silver-alum inium alloys eontaining 0- 11% a lu m inium w as revised from th e re su lts o f X -ra y an aly sis a t o rd in ary an d high tem p eratu res, electrical resistan ce m easurem ents, a n d microscopie exam ina- tion. Alloys eontaining 5-7-8 an d 2% alum inium undergo th e eutectoid an d tho m e ta te c tic tran sfo rm atio n a t 615° an d 420° C., respectivelv. W hile th e m etatectic tran sfo rm atio n can easily be suppressed b y quenching in w ater,
6 M etallurgical Abstracts
Vo l, 3 com plete suppression o f tho eutectoid tran sfo rm atio n is scarcely possible.T h u s, th e alloys quenched from tho (3 field alw ays consist o f th o y-phase, su p e rsa tu ra te d w ith silyer, showing th e diffraotion lines belonging to th e hexagonal close-paclced la ttic e . On h eatin g , th e ąuenched hy p o -eu teeto id alloys, a n anom alous inerease o f resistance w as observed a t a b o u t 200° C., w liieh is considered to be d u e to th e form ation o f a com pound Ag3Al. Tho c ry s ta l stru c tu re o f th e /3-phase w as determ ined b y X -ra y a n aly sis a t high tem p eratu res. As an ticip ated , th is p h ase has a body -cen tred cubic la ttic e , th e p a ra m e te r o f w hich is 3-295 A. a t 700° C. (Al = 7-9S%).— S. G.
*The E lectrical Resistance of Hydrogen-Cliarged T antalum W ire. A.
S ieverts a n d H . B riining (Z. physikal. Chem., 1935, [A], 174, 305-369).—T he ab so rp tio n o f h ydrogen a n d th e change in resistance produced th ero b y in a ta n ta lu m w ire havo been d eto n n in ed a t 400°-600° C. a n d a t pressures from 1 a tm . upw ards. A t 500°-600° C. th o dissolved hydrogen is ex actly propor- tio n a l to th e sąu are ro o t o f tho pressures, b u t appreciable d ev iatio n s ocour a t 400° C. T he increaso in resistance is in all cases pro p o rtio n al to th e a m o u n t o f hydrogen absorbed. Tho phenom ona observed in th e ta n ta lu m -h y d ro g o n sy stem are th u s sim ilar to those in tho p a llad iu m -h y d ro g en s y s te m ; in bo th cases th e relationships observed are in conform ity w ith th e aboye law s as long as no new phase is form ed.— B. BI.
*Deeaying Interm etallie Compounds. G. T am m an n a n d A. Iliilienbeek (Z. anorg. Chem., 1935, 223, 288-296; a n d (sum m ary) Light M etals Research, 19 3 5 ,4 ,2 0 -2 4 ).—T he in term etallie com pounds of som e m etals w ith alum inium , Silicon, calcium , m agnesium , a n d cerium decom pose on exposure to m o ist a ir owing to th e reactio n o f th e above-nam ed m etals w ith th e m oisture to form hydroxides, th e o th er com ponent o f th e com pound being lib erated as finely diyided m e ta l; exam ples discussed are th e com pounds FeA l3, AISb, PbC a, AgCa, SnMg2, a n d BiCe. On th e o th e r h a n d no such reactio n occurs w ith such com pounds as Al3Mg4 a n d AuMg. T he difierence in b ehaviour is a ttrib u te d to th e form ation o f a non-porous, p ro tectiy e film in th e la tte r, a n d th e non-form ation o f such a film in th e form er case.— A. R . P .
*Exam ination of the Law of Mass Action of Coneentrated M olten Solutions by Potential M easurements. F . N e u b e rt a n d F . S auerw ald (Z. physikal.
Chem.., 1935, [A], 174, 161-198).—T he eąu ilib riu m c o n sta n ts a n d a c t m t y relationships in tho reaction o f m etals w ith th e ir m olten sa lts w ere deter- m ined by m easurem ents o f th e eleetroehem ical p o to n tials in order to coniirm tho co n stan ts determ ined an aly tically , th e corresponding aetiv ities a n d th e m oleeular woiglits derived from th e re su lts. I n p ractically all cases tho L o ren z-v an L a a r m ass action law does n o t apply, th e sm allest d ev iatio n s o f th e m ean yalues o f th e co n stan ts from tho id eał m ass action law being a b o u t 25 % . T he following reactions w ere exam ined : lead w ith m olten ti n a n d silver ohlorides an d w ith silver brom ide a n d io d id e; lead chloride w ith th alliu m , zinc, a n d cadm ium ; cadm ium a n d stan n o u s chloride; a n d th alliu m a n d cadm ium chloride.— ]3. BI.
*On a New Method of Determ ining Transform ation Points [Solidus of Copper- Silver Alloys]. H . N ipper a n d E . L ip s (Z. M elallkunde, 1935, 27, 242-243).—
Changes in th e stru c tu re of alloys a t high tem p eratu res are u su ally accom panied b y sudden changes in th e m echanieal properties. A n a p p a ra tu s h as been co n stru cted , therefore, to determ ine th e torsion of w ires a t g rad u ally inereasing tem p eratu res w ith a u to m atic reg istratio n o f tho re s u lts ; tho m ethod w as applied to th e determ in atio n of th e solidus o f eopper-silyer alloys.—A. R . P .
Stereo-Chemistry of Solids. W ilhelm B iltz (Ber. deut. chem. Ges., 1935, [A], 68, 91-108).—T he space occupied b y tho a c tu a l p articles o f a solid m ay be approxim atcly represented b y th e sum o f single inerem ents each bearing a definite relationship to th e n a tu rę a n d condition o f th e corresponding particie. T h e principle is applied to tho case o f c ertain glasses, th e d en sity
1936
I I I . — Structure 7
of w hich can bo accu rately p red icted from th e ir com position, a n d o f 2 series o f interm etallic com pounds, in w hich “ noble ” a n d “ baso ” m etals, respect- ively, propondorato, T he a d d itiy e c h a ra c te r o f th e increm ents r a th e r th a n of tho atom ie yolum es esp lain s th e strik in g discrepancies betw een observed a n d calculated m oleeular yolum es i n tlio la tte r case. T liis is fu rth e r illus- tr a te d b y references to th e a lk ali m e ta l am algam s. T he p articles o f in ter- m etallic com pounds are com pared to m a te ria ł in a s ta tc o f m echanieal eom- pression, an d th e accom panying co n tractio n in eleetronic volum e is fu rth e r related to y ariatio n s in th e ionio charges. T he eonception o f tho space-lattiee is exam ined, from tho sta n d p o in t o f spaee increm ents.— P . M. C. R .
I I I — ST R U C TU R E
(M etallo g rap h y ; M acro g rap h y ; C rystal Struoture.)
*Statistical Investigations of the Structure of M etals.—I. E . Schoil (Z.
M eiallkunde, 1935, 27, 199-208; discussion, 208-209).—M athom atical pro- cedures for calculating th o are a a n d yolum e occupied b y th e yarious con- stitu e n ts o f m etals a n d alloys are deseribed w ith reference ehiefly to fetTous m etals.—A. R . P .
tR elatio n Between Diffusion an d Structure of Solid Alloys. W . S eith a n d A. K eil (Z. Meiallkunde,, 1935, 27, 213-215).— R eeen t w ork o f th e a u th o rs an d others is review ed in a n a tte m p t to o b ta in a re la tio n betw een th e m ovem ent o f atom s in sohd solutions an d o th e r p ro p erties o f th e alloys. T he a m o u n t o f m ovem ent depends on th e chem ical affinity betw een, a n d th e size of, th e com- p onent ato m s, an d its dependence on th e re la tiv e eo n cen tratio n s o f th e com- p onent ato m s is in m an y cases d eterm in ed b y th e m elting p o in ts. Diffusion is appreciably inereased b y recry stallizatio n a n d b y tra n sfo rm a tio n s; in m o st cases to o th e passage o f a d irect e u rre n t th ro u g h th e alloy eauses th e com- ponents to diffuso in opposite direetions (electrolytic m igration).— A. R . P .
*Detection of M etallographic Processes by R adioactiye Methods. O. W ern er (Z. M eiallkunde, 1935, 27, 215-219).—T he diffusion o f rad io actiy e em an atio n s th ro u g h a m etal la ttic e is rc g u la te d b y tho la ttic e y ib ratio n s o f th e m etal an d hence th e courso o f tho te m p e ra tu re -ra d io a e tiv ity curve o f a m etal con- tain in g a rad io actiy e su b stan cc, e.g. thorium -JC, is determ ined b y th e freąu en cy an d am p litu d ę o f tlie atom ie m ovem ents in th e m etal. T he te m p e ra tu re coeff. o f ra d io a c tiv ity o f d ifiere n t m etals is inyersely p ro p o rtio n al to th e ch aracteristic te m p e ra tu re o f D ebyc’s th eo ry o f solid bodies. D eterm in atio n o f th is coefl. affords a m eans for calculating th e energy absorbed in rolling a m etal in to sh eet (th is is illu s tra te d b y experim ents on gold), fo r calculating th e a m o u n t o f dissolved h ydrogen in tho m e ta l (illu stra te d b y experim ents on electrolytic copper), for determ ining tho tra n sfo rm a tio n p o in t o f m etals (illu strated by curyes for th alliu m an d iron), fo r determ ining th e Curio p o in t (of iro n a n d niekel), a n d for stu d y in g th e courso o f th e sin terin g process w ith com presscd m etal pow ders (illu stra te d b y experim ents on m olybdenum a n d carbonyl niekel).—A. R . P .
*fThe L attice Constants of Beryllium . E . A. Owen a n d Llew elyn P ick u p (Phil. M ag., 1935, [vii], 20, 1155-1158).—R ed eterm in ed yalues o f th e la ttic e co n stan ts a t 18° C., o f annealed beryllium o f vcry hig h p u rity (Fe, 0-01% ; 0 , 0-0 5 % ; N , 0 '0 0 5 % ; a n d traces o f sihcon a n d alum inium ) are : a — 2-28105 A .; c (axial ra tio ) = 1-5682. T hese yalues are in close agreem ent w ith th e a u th o r’s preyious yalues a n d differ som ew hat from those o f o th er experim enters.—J . S. G. T.
tT h e X -R ay Pow der Photography of Alloys. A. J . B rad ley (M ełallurgia, 1935, 13, 69-70).— A condensed re p o rt o f a lectu re to th e M idland M etal- lurgical Societies. T he use o f X -ra y pow der p h o to g rap h y , as com pared w ith
8
Metallurgical Abstracts
Vo l. 3photom icrography, in ostablishing th e equilibrium diagram s o f tho alloy sy stem s is considorcd. Tho m eth o d o f spacing d eterm in atio n is briefly dcsoribed a n d tho applioation o f la ttic e space m easurcm ents in determ ining accurato coeffs. o f oxpansion referred to . Tho influence o f h e a t-tre a tm e n t 011 X -ra y p h o to g rap h y in giving riso eith er to com pleto phase changes o r to atom ie d istrib u tio n is discussed w ith p a rtic u la r rcference to tho nickel-alum inium , copper-alum inium , a n d iro n -alu m in iu m system s.— J . W . D.
*Precise D eterm ination of Anglcs and L attice Constants by the D ebye- Scherrer Method. M. S trau m an is a n d A. Iey in ś (N a lu r w is s., 1935, 23, 833).— T he u sual m eth o d is modified in tlia t th e eńd of th o film is placed a t an angle o f 90° in ste a d o f a t 0° o r 180° to th e p rim a ry X - r a y ; b y m easuring tho interference rings w ith sm ali a n d large d th e p o in ts o f entraneo a n d e x it o f th e X -ra y beam can bo determ ined a n d lience th e e x a c t d iam eter o f tho cam era. Tho la ttic e p a ra m e te r o f sodium chloride w as found to bo a = 5 ’6264 ± 0 0003 A.— B. BI.
I V — CORROSION
*Inhibiting Additions to Solutions W hicli A ttack A lum inium . II. R ohrig (A lu m in iu m , 1935, 17, 559-562).— R ead before th e V II Congres In te rn a tio n a l des Mines, do la M ćtallurgie, e t de la Gćologie, P a ris, 1935. V arious sub- stan ces w hich in h ib it th e action o f m inerał acids on ferrous alloys also in h ib it or g re a tly reduco th e ra te o f a tta c k o f acids on alum inium a n d its alloys, tliu s a d d itio n o f 1% o f nicotine su lp h ate to 20% hydrochlorie aeid reduces th e loss in w eight o f p u re alum inium th erein from 239 to 3-8 g rm ./m .2 in 15 m inutes, whilo 0-1% o f dibenzyl sulphido in 10% hydrochlorie acid reduces tho loss in w eight from 77-1 to 2-8 g rm ./m .2 in 90 m inutes. Still moro effective is th e in h ib ito r know n as “ Sparbeize 2 0,” ad d itio n o f w liich to Ar-hydrochloric acid reduces its a tta c k on p u re alum inium from 532 to 0-15 g rm ./m .2 in 6 lirs.
—A. R . P .
♦Comparison o£ the R esistance to Corrosion of 11 Light Alloys under N atural and L aboratory Conditions. E . K . O. S chm idt a n d E . Boschel (L u ftfahrt- forsćhunt7, 1935, 12, 116-120).—T ests w ere carried o u t in th e lab o rato ry by th e D .V .L. m ethod a n d u n d e r n a tu ra l conditions in th e N o rth Sea on th e beliaviour o f yarious grades o f D u ralu m in , K .S .-S eew asser alloy, H ydro- nalium , A nticorodal S, an d Silum in. T he resu lts showed t h a t th o lab o rato ry te s ts provide a com parative guido to th e resistance to corrosion u n d er prac- tical conditions in a b o u t ^ o f th e tim e. T he alloys te s te d fali in to 3 groups : (I) those w hich show appreciable red u ctio n in s tre n g th in sea-w ater in a b o u t a fo rtn ig h t—D u ralu m in 681 ZB, D uralum in 681 A, a n d D u ralu m in 681 H ; (II) thoso w hich sufler a loss in stre n g th on ly a fte r 6 m o n th s’ cxposure—
Silum in, A nticorodal S ; a n d (I II) those w hich rem ain p ractically unaffected fo r 2 y ears—D u ralu m in 681 K , D u ra lp la t, K .S.-Seew asser, a n d H ydronalium .
—A. R . P.
*On th e Corrosion-Resistance o£ H ydronalium Especially A gainst Sea- W ater. G. Siebel (A lu m in iu m , 1935,17, 562-567).— H y d ro n aliu m alloys w ith m agnesium 7-12 a n d m anganese 0-3-0-5% haye a high resistan ce to sea- w ater w hich is p ractically th e sam e in tho c a st (heterogeneous) sta to as in th e hom ogenized condition. A fte r cold-work, how ever, th e liomogenized alloys become unstablo a t tem p eratu res o f 60° C. an d higher a n d th e new p h ase p recip itated a t tho grain boundaries in a highly dispersed form induces serious in tercry stallin e corrosion in salt-w ater. B y tem p erin g a t tem p eratu res ju s t below th e so lu b ility line to o b tain a heterogeneous s tru c tu re w hich is stab le th is s e n s itm ty to in tercry stallin e corrosion on w arm ing is en tirely rem o v ed ; a sim ilar eilect is produccd b y sm ali ad d itio n s o f zinc, ealcium ,
1936
I V .— Corrosion 9
Silicon, tifcanium, o r chrom ium w hich m ore o r less stabilize th e liomogcncous s ta te o r a t least ren d er i t inscnsitive to tem pering.—A. R . P.
*The Corrosive Action of Sulphur 011 Metallic Copper D uring V ulcanization.
Shozo S atak e (J. Soc. Rubber In d . Ja pan, 1935, 8, 461—471; C. A bs., 1935, 29, 8403).— [In Jap an cse.] T he corrosive action o f com pounded su lphur was stu d ied b y keeping copper an d a ru b b e r p la te in c o n ta c t during yulcaniza- tion. T he corrosion can bo expressed b y th e eq u atio n x = K t", w hero x is th e e x te n t o f corrosion in t hrs., a n d K a n d 11 are constants depending on the conditions o f te s t. T h a t n is inversely p ro p o rtio n al to th e yelocity const. of yulcanization, w hich in tu m is related only to th e tem p eratu ro o f yulcaniza- tio n an d th e kin d a n d a m o u n t o f accelerator, w as confirmcd b y te s ts o f th e speed o f yulcanization o f th e sam e ru b b e r sam plo u sed in th e corrosion te st.
K is directly pro p o rtio n al to th e su lp h u r used in com pounding (% b y volutne).
The relation betw een K an d th e veloeity const. o f yulcanization w as also studied. T he corrosive actio n o f com bined su lp h u r (acetone-insoluble su l
phur) in vulcanized ru b b e r on copper is w eak, an d corrosion o f copper during yulcanization is due m ainly to th e presence o f free sulphur. T he ra tio o f form ation o f sulphides w as : Cu2S : CuS = 5 : 3 , a n d th is ra tio rem ained nearly const. an d w as n o t infłueneed b y changing th e percentage o f su lp h u r or accelerator.—S. G.
Influence of Sugar in th e Corrosion o£ [Tinplate by] Canned Fruits. E . F . K ohm an a n d N . H . Sanborn (Canncr, 1935, 80, (9), P a r t 2, 111-112; O.
A bs., 1935, 29, 0319).—I n generał, th e re is less Container corrosion a t th e higher sugar sy ru p eoncentrations. Sugars in canned fru its decrease corrosion as com pared w ith non-sugar packs. I n b o th a citric acid -so d iu m c itra te solution an d in g rap e-fru it juice th e ad d itio n o f 25 o r 50% dextrose, sucrose, or lcvulose definitely inereased th e H -ion conccntration o f th e solution. I t appears probable t h a t sugars com bine chem ically w ith som e o f th e fr u it constiriients.—S. G.
*Influence of Various Acids on Corrosion [of Tinplate] in Prepared Prunes.
E. F . K ohm an an d N . H . Sanborn (Canner, 1935, 80, (9), P a r t 2, 112; G.
Abs., 1935, 29, 6319).— T he a b ility o f various organie a n d inorganic acids to p rev en t o r re ta rd corrosion of tin p la te by canned prunes w as determ ined.
Suflicient o f eaeh aeid w as added to low er th e p n from 4-05 to 3-84. Citric acid gave th e b e st results. T his aeid possesses th e tendency to form complex ci tra to ions w ith m etals.— S. G.
"Influence of Various Acids on Corrosion [of Tinplate] in R oyal Anne Cherries. G. S. B o h a rt (Canner, 1935, 80, (9), P a r t 2, 114; O. A bs., 1935, 29, 6318).—T he prin cip al acid produced by flat-sour b a c te ria in canned cherries is lactio acid. T he a c id ity o f th e expcrim ental p ack o f cherries w as ad ju sted to p n 3-5 b y th e ad d itio n o f citric, lactic, phosphoric, m alic, acetic, an d b u ty ric acids. T he g re a te st loss o f vacuum in th e cans owing to co r
rosion w as caused b y phosphoric acid. T here is a considerablo n a tu ra l p hosphate in th ese cherries.-—S. G.
*Corrosion Tests of Metals Used in Pea Processing. F . L. LaQ uo (Canning Age, 1935, 16, 385-387, 406).— Copper, nickel, tin , zinc, c a st tin -b ro n ze , 2 an d 1 brass, 50 : 50 so ft solder, Monel m etal, a n d 18% nickel silver were investigated. S ets o f specim ens w ere exposed in b rin e ta n k s j pails o f w et peas, a n d o th er positions in a w orking pea-canning p la n t. T he cffect o f 2, 6, 10, 20, 30, 50, a n d 80 p.p .m . o f th e m etals chrom ium , copper, iron, nickel, tin , an d zinc on th e colour a n d flayour o f canned peas w as also determ ined.
— C. E . H . U nderground Corrosion. K . H . L ogan (Proc. Am er. Soc. C ivil E ng., 1935, 61, 317-329; discussion, 591-594, 919-923; B u ilŁ S ci. A bs., 1935, 8 ).—A su m m ary o f tho conclusions reached b y th e N atio n al B u reau o f Stancłards (U.S.A.), as a re s u lt o f th e corrosion o f pipes in soil (see M et. A bs. (J . ln s t.
10 M etallurgical A bstracłs
Vol. 3 M etals), 1931, 47, 6 6 5 ; M it. A b s., 1934, 1, 242) leads to a diseussion o f tho c h aracteristics an d courso o f such corrosion, an d tho m eans available for reducing corrosion losses. F u rth e r resoarch in th is field is urged. 25 refer- ences are given.— S. G.The Corrosivity o! Soiłs. --- (N a t. B u r. Stand. Leiler Circular N o. 433, 1935, 13 pp.).— Givcs a b stra c ts an d sum m aries o f re p o rts relatin g to investi- gations o f th e corrosion o f fcrrous a n d non-ferrous m aterials b y soils.—S. 6 .
Corrosion of Metals. N athalio Goldow ski (L a N aturę, 1935, (2955), 5 4 0 - 5 4 2 ; (2957), 6 9 -7 2 ; C. A bs., 1935,29,7920).— Seycral new m aehines h ave been devoloped for a lte rn a te im m ersion o f m etallic p lates in te s t solutions. The electrochem ical phenom cna involved in th e corrosion o f m etals a n d resu lts o f y ariatio n s in oxygen c o n tac t are associated w ith th e ra te o f corrosion.— S. G.
V.— PRO TECTIO N
♦Influence of the W orking Conditions in Tinning on the Porosity of Tinplate.
F ritz P e te r an d Georges Le G al (Arch. Eisenhiitlenwesen, 1935-1936, 9, 2 85- 287; diseussion, 288-291).—N um erous te s ts extending over a long period o f large-scale tin n in g operations h av e shown t h a t no single facto r h as a deter- m ining influence on th e poro sity o f tin p la te . T he m ost im p o rta n t factors are absolute cleanliness o f th e steel, th e thickness o f th e tin coating, th e n a tu rę o f th e pickling process, an d th e p u rity o f th e flux. A bsorption o f hydrogen from th e pickling o peration does n o t a p p e a r to p la y th e im p o rta n t p a r t in producing p o ro sity u su ally ascribed to it. T he m inim um thickness o f tin to g uarantee a bsolute freedom from p o ro sity u n d e r correct w orking conditions is a b o u t 100 g rm ./m .2. In th e diseussion IF. H . Creutzfdd sta te d t h a t before m aking te s ts for p o ro sity all grease m u st bo rom oved from th e su rfa c e ; th is can be dono m ost efTectirely b y w ashing w ith trichlorethylene w hich h as no aetion on th e tin , w hereas alkalino cloaners a tta c k tho m etal a n d produce new pores. The b e st m ethod for d etec tin g pores consists in coating tho m etal w ith a w arm (60° C.) solution o f p o tassiu m ferrocyanide in 10-15% ag ar-agar containing 0-5-1% o f sodium chloride. O th er speakers producećl evidence in favour of th e th e o ry t h a t surface im p u rities on th e iron aro tho ch ief c a u s e o f p o ro sity in tho tin p la te .—A. R . P .
tCopper W ire Tinning. Ch. B ernhooft (Z. M etallkunde, 1935, 27,264-266).—
Tho ti n coating applied to copper wire to p re v e n t its being a tta c k e d b y sulp h u r durin g v ulcanization o f tho in su latin g ru b b e r coating subsequently applied m ay be fa u lty owing to one o r moro o f tho following causes : incom plete rem oval o f th e acid used in pickling before passing th e w ire througli th e b ath , too high a te m p e ra tu re o f tho tin b a th w hich resu lts in dissolution o f 5 % or moro o f copper, too tliin a coating duo to a Iow b a th te m p e ra tu re o r too ra p id passage o f th e w ire througli tho b a th , o r insufficient cleaning o f th e copper.—A. R . P .
Hot-G alvanizing. H and Galvanizing of Smali Pieces : Galvanizing by the U sual Method. A. F o rn y (Oalvano, 1935, (35), 26-27).—D escribes briefly tho m ain features o f th e m ethods used in F ran ce for galvam zing sm ali p a rts b y h an d , condem ning th e em pirical co n tro l a n d inefficient w orking w hich ap p ear to bo u su al in th is field. A b rig h t finish w ith o u t spangles is b e st for sm ali pieces. T h is is o b tain ed b y add in g 0-015% each o f ti n a n d alum inium to th e b a th , a n d w orking a t a b o u t 470° C. F o r h o t-d ip galvanizing a liighly ex- perienced stafT is rcąu ired . T he e ą u ip m cn t is briefly outlinod.—C. E . H .
Lead and Tin in Zinc Used for Galvanizing. W ern er F ró lich (lllu s t. Zeit.
Blechinduslrie, 1935, 64, 1298-1299, 1323-1324).—R em oltcd zinc u su ally co n tain s appreciablo profiortions o f tin an d lead, p robably deriyed from solder : th e tin c o n te n t m a y be reduced to 0-3-0-4% b y m eans o f su lphur, b u t F .
1936
V .—Protection 11
considers th a t sm ali ad d itio n s o f m etals o th er th a n zinc ren d er th e m a te ria ł less corrodible a n d less susceptiblo to e m b rittlem en t or discoloration, e.g. b y antim ony, th a n is p u re zinc. H e recom m ends a com position o f lead 1, tin 0-6; iron 0-12, cadm ium 0-07, alum inium 0-01% , an tim o n y a tracę, and rem ainder zinc, fo r usc in galvanizing b atlis, th e tem p e ra tu re o f w hich recjuires very careful control.—P . M. C. R .
*0n the Reactions o£ Iro n w ith Liciuid Zinc [at Galvanizing Temperatures].
W ilhelm Piingel, E rich Sclicil, a n d R o b e rt Stenkhofi (A rch. Eisenhilttenwesm , 1935-1936, 9, 301-304).—Tho a ttn c k on iro n b y m olten zinc a t galvanizing tem p eratu res can tak o place in tw o w ays, eith er (I) FeZ n3 is form ed a n d th e rato o f dissolution o f th e iro n is sm ali a n d increascs slig h tly w ith increase in tem peraturo, o r (II) F eZ n , is tho prin cip al p ro d u c t o f th e reaction, being formed as loose m asses o f needle-liko c ry sta ls w hich allow th e zinc to como into co n tac t w ith fresh iro n surfaccs, a n d th u s a tta c k on th e iro n is sovero. I n case (I) a denso p ro tectiv e lay er is form ed on th e iron, a n d tho reaction soon becomes v e ry slow a t c o n sta n t tem p eratu re, w hereas in case (II) a v e ry th ic k non-protectivo lay er is form ed w hich som etim es assum es rem arkable c ry s ta l shapes, several exam ples o f w hich are illu strated . Abovo a cerfcain definite tem peraturo depending on th e n a tu rę o f th e steel F eZ n3 is alw ays form ed, b u t below th is tem p eratu ro eith er com pound m a y bo form ed according to th e conditions. T he presence o f carbon a n d copper in th o steel seems to favour case (II) w hereas tho presence o f chrom ium a n d alum inium seem s to favour case (I).—A. R . P.
*Metallic Cementation. V II.—Metallic Cementation [o! Iron, Niekel, and Copper] by Meaus of Manganese Powder. T su to m u K aso (K in zo ku no K en kyu , 1935, 12, 478-183).— [In Jap an ese.] Tho cem entation o f iron, niekel, a n d copper b y m anganese in th e form o f th e pulverized com m crcial p ro d u c t a t various tem p eratu res betw een 600°-1100° C. for 1, 2, 3, a n d 5 lirs. w as in- vestigated. T he hardness an d d o p th o f p en etratio n o f tho surface lay er o f th e cem ented specim ens w as m easured, a n d m icroscopic exam ination, chem ical analyses, a n d corrosion te s ts w ith stro n g acids w ere also carried o ut. M an
ganese diffuses in to iron, niekel, an d coppcr a t a tem p e ra tu re above 600° C., th e ra tę o f diffusion inereasing w ith increase o f tem p eratu re. I n th e caso o f iro n th e ra to o f diffusion inereases alm o st a b ru p tly a t th e ^13 p o in t (906° C.).
The relation betw een th e increase in w eight o f th e specim ens a n d th e absolute tem peraturo o f cem entation o r tho length o f tim o for th e tre a tm e n t is given b y a n exponontial funetion as previously show n (M et. A bs., 1935, 2, 165, 385, 463, 522), Tho surfaccs o f iron a n d niekel cem cnted w ith m anganese aro easily a tta c k e d b y stro n g aeids, b u t t h a t o f copper is unaffected b y diluto sulphuric a n d hydrochloric acids o r concontrated hydrochloric acid.—Ś. G.
[Metal Spraying in] Oil-Field and Refinery Practice in Foreign Countries.
W illiam R eid (.MelaUizer, 1935, 4, (1), 2 -5 , 13).—R . lists tho p a rts o f oil- refinery p la n t w hich h ave been successfully tre a te d b y th e m o tał spraying process. T he artielo deals m o stly w ith th e building u p o f sliafts, &c., w ith steel, b u t thore is also a description o f som e w ork carried o u t b y th o spraying o f Monel m etal, zinc, a n d “ alum in iu m -b ro n ze.” —-W. E . B.
M etallizing New Reflnery Vessels. G. M. Jack so n (Melallizer, 1935, 4, (1), 11).—A description o f th e use o f m etal spraying for th e p ro tectio n o f condensers in oil refinery. T h e coating is 2 lb ./ f t.2 o f m etal sp ray ed (lead), a n d th e coating is applicd b o th to th e v ap o u r a n d th e w a te r side o f th e condenser.—W . E . B.
Protection A gainst B urning-O ut by Means o! the “ A lu m e n t” Process.
--- (Illust. Zeit. Blechindustrie, 1935, 64,1389-1390).—T he process consists in annealing a t 900°-1100° C. th e (ferrous) m aterials to be p ro tected , a fte r sp ra y ing w ith a lu m in iu m ; a special flux is p ain ted over th e sp ray ed m etal, w hich i t p ro tects from oxidation in th e early stages, w h iłst assisting its p en etratio n into
12 M etallurgical A b słra d s
Vol. 3 tho iron when com bination occurs. A h ard a n d rc s ista n t ooating o f FeA l3 is said to be produeed : i t is claim ed th a t tro a tm e n t o f a n “ A lum ent ” -treatcd iro n surface a t 1000° C. for 1400 hrs. produeed no appreciable alteratio n in stru c tu re . T hin-w alled articles should bo tre a te d w ith spccial light alloys, as th e b rittlen ess o f FeAL, w ould causc a n u ndue decrcase in stren g tli.—P . R .A nti-R ust P aints Containing Coal-Tar and Alum inium Powder. --- (A n n . Ponts Chaussecs, 1935, 105, 286-288).—A n account is given o f com parative te s ts on ta r-a lu m in iu m p ain ts a n d red-lead. T he te s ts included exposuro to.
ultra-v io let rad iatio n , salt-sp ray , freezing, m o ist a n d d ry b eat, a n d im m ersion in w ater. B o th th e d u ra b ility a n d th e coyering pow er are s ta te d to have p rovcd sup erio r in tho case o f th e ta r-a lu m in iu m p a in t.—P . M. C. R .
A lum inium Paints. B erth o ld W in te r (Petroleum Z ., 1935, 31, (44), 8).—
A lum inium p a in t is stab le an d effeetive a t te m p eratu res u p to 1000° C . : its high reflecting pow er renders i t a useful p ro tectiv e m edium for fuel ta n k s an d containers, w here a Iow tem p eratu ro is d e sira b le ; i t affords valuable protection ag a in st r u s t even w hen u sed in conjunction w ith o th e r pigm ents, a n d i t resists a tta e k b y am m onia an d hydrogen sulphidc. I t is also recom m ended as a prescrvat,ive fo r wood.—P . M. C. R .
Im proved P aints Spur A ttacks on Corrosion Problem s. J . O. H asson (Steel, 1935, 96, (10), 30-33).-—T he p re p a ra tio n o f th e surface to w hich th e y are to be ap p lied is o f p a rtic u la r im portancc in connection w ith anti-corrosion p a in t ćoatings. G alvanized iron is b e st first roughened b y etching w ith a n acid solution, or b y exposurc to th e w eatlicr for some m onths. A good p rim er for galvanized iron is a zinc d u st-z in e oxidc pa!int.—S. G.
V I.— E LEC TRO D EPO SITIO N
F aulty Chromium Plating, Its D etection and Rem oval. R a lp h W. H arbison (M eta llw a ren -Iiu l. u . G a lm n o -T ech ., 1935, 33, 521-522).—F o r chrom ium p late d irect on iron or stecl th e fcrro x y l te s t o r sim ple im m ersion in copper sulphate solution ra p id ly d ctec ts p o ro sity b u t for chrom ium p la te on niekel, copper, or brass undereoats i t is preferable to m ake th e article th e cathode in acid copper su lp h ate solution, copper being deposited only on th e porous p a rts. T he best m etiiod for strip p in g fau lty chrom ium p late consists in dissolving th o chrom ium anodically in 3-5-4% sodium hydroxide so lu tio n ; th e p latin g m ay bo strip p ed moro ra p id ly in h o t hydrochloric acid b u t th is produces severo etching of ferrous o r copper-base m etals.—A. R . P .
The New Methods of Niekel Plating. E . S taurenghi (Induslria meccanica, 1935,13, 702-704; C. A bs., 1935, 29, 7821).—P resen t niekel p latin g processes aro review ed, a n d degreasing a n d cleaning m ethods are described. T he niekel c o n te n t o f th e b atli is a b o u t 40 -5 0 g rm ./litre ; cu rrc n t d e n sity 0-3-0-4 a m p ./
d m .2 while fo rra p id plating m ethods 1-3 a m p ./d m .2 are em ployed. T he b atli is s tirre d a n d th e picces are m oved to ob v iate stre a k s on th e d e p o sit; p n is 5-S-6-2. F o r ra p id niekel p latin g th e following b atli is recom m ended : pu re niekel su lp h ate 22-5 k g .; pu re am m onium su lp h ate 2-0 kg., pu re niekel chloride 0-5 kg., p u re sodium p erb o rate 0-5 kg., w a te r 100 li tr e s ; 35°-40° C., voltage 2-75-3-5.—S. G.
Testing of Niekel Plate [on Steel]. (Liebetanz.) Sce p. 15.
* 0 n th e Polarization Potential in th e Cathodic Deposition of Zinc from Aąueous Solutions of Zinc Sulphate. T o m im atu Isiliara, Takeo O noda, an d K a tu o U m etu (K in z o k u no K e n b ju , 1935,12, 381-396).—[In Jap an ese.] The cathodic polarizatio n p o ten tial, anodic overvoltage, an d to ta l polarization p o te n tia l in th e electrolysis o f aąucous solutions o f zinc su lp h ate o f different concentrations, acidificd w ith sulphuric acid an d w ith th e ad d itio n o f various am o u n ts o f glue o r g elatin , were m casured b y a d irect m ethod w ith a norm al
1936
V I I .— Electrometallurgy and Electrochemistry 13
calomel electrodc a n d a p o tcn tio m eter. T he anodę consisted o f a platinized p latin u m plate, b u t th e s ta rtin g cathode w as a zinc-plated p la tin u m plato haying a n in n er lay er o f copper. E x c c p t th e active surface o f tlić cathode, all portions of i t w ere eovered com pletely w ith lead glass b y fusion. T he effects o f eu rren t d en sity an d th e com position o f th e solution on th e ą u a n titie s referred to above were also m easured. All th e experim ents w ere carried o u t a t 35° C.
111 an eleotrie th e rm o sta t o f large cap aeity .— S. G.
Non-Poisonous Plating B aths. K . A ssm ann (Ohem.-Zeit., 1935, 59, 9 0 4 - 905).— Owing to th e highly poisonous n a tu rę o f th e coraponents m an y a tte m p ts have been m ade in re c e n t years to replace cyanide p la tin g b a th s w ith those eontaining non-poisonous salts. S atisfaeto ry resu lts have been o b tain ed in silver- a n d copper-plating b y th o use o f solutions o f th e iodides in concen- tr a te d alkali iodide solutions. F o r silver th e b a th eontains p o tassiu m iodide 450, silver iodide 45, liydriodic aeid 15, an d gelatin 3—1 grm . dissolved in 800 e.e. o f w ater, an d for copper p otassium iodide 550, cuprous iodide 55, hydro- clilorie acid 10, a n d g elatin 3-5 grm . in 1 litre o f w ater. T he b a th s aro o p erated a t 20° C. w ith 0-5-1-5 am p./dm .'- a t 0-2-0-5 v. an d yield line-grained a d h e re n t deposits on copper, b rass, nickel silver, a n d sim ilar alloys. M uch less expen- sive b a th s w hich y ield b rig h te r deposits th a n those o b tain ed from cyanide b a th s are prep ared b y dissolving 33 grm . o f silvcr th io e y a n a te o r 43 grm . of cuprous th io ey an ate in 1 litre o f 20% sodium th io e y a n a te solution eontaining 1% o f sodium sulphite. Silver has also satisfaeto rily been p la te d from n itra te solutions eontaining thiourca. N o good non-poisonous b rass p la tin g b a th has y e t been dcveloped b u t good eadm ium a n d zine deposits can be o b tain ed from su lp h ate b a th s a n d good chrom ium deposits from solutions o f yiolet chrom ie ehloridc using soluble chrom ium anodes a n d superim posed a lte rn a tin g e u rre n t to overcom e tho p assiv ity o f th e anodes.—A: R . P.
tB rig h t Electrolytic Deposits. M ax S ch lo tter (Z. M etallkunde, 1935, 27, 236-237).—E lectrodeposited m etals are never ab so lu tely p u re, sm ali am o u n ts o f tho anion o f hydrolysis p ro d u ets o f th e salts in th e electrolyto or o f various a d d itio n agents being p ractically alw ays included in th e deposit. Tho stru c tu re o f th e deposit as reg ard s grain-size an d ra te o f g row th is eontrolled ehiefly b y th e n a tu rę o f th e anion, w ith inereasing m olecular volum o o f w hich th e rato o f grain-grow th deereases a n d th e n u m b er o f crystallization nuelei inereases. U n d er su itab le electrical conditions, inclusion o f anions in th e lattice stru c tu re o f th e deposited m e ta l m ay be induced a n d th e ap p earance tliu s considerably modified. W orking along these lines considerable advances liave recen tly been m ade in th e p roduction o f b rig h t deposits o f eopper, silver, gold, nickel, an d chrom ium . B rig lit nickel deposits co n tain inclusions o f oxide, are n o t passive like m a tt deposits, a n d can read ily bo chrom ium p la te d ; m a tt an d b rig h t deposits o f nickel form a therm o-elem ent th e e.m .f. o f w hich is 2-5 X 10-« v ./° C.—A. R . P .
The Im portanee o! R egularity iu th e Crystal S tructure of Thick Electrolytic Coatings. W . M uller (M etalhm ren-Ind. u . Galiano-Tech., 1935, 33, 4 7 7 - 478).—T he factors influeucing th e stru c tu re o f electrolytic deposits are eritically discussed an d th e ir influence on th e p roduction o f th ic k (0-5-5 m m .) deposits w ith a reg u lar stru c tu re th ro u g lio u t is outlined, th e im portanee o f correct b a th com position, s ta n d a rd electrical conditions, a n d absolute cleanli- ness being stressed.—A. R . P .
V I I — ELE C T R O M E T A L L U R G Y A N D ELE C T R O C H E M IST R Y (O ther th a n E lectrodeposition.)
*Polarization of Electrodes in the Deposition of Metals from Solutions of Complex Cyanides. O. E ssin a n d A. M atanzew (Z. physikal. Chem., 1935, [A], 174, 384-394).—M any opinions liave been expressed in th e lite ra tu re as to th e
14 M etallurgical A bstrads
Vol. 3 n a tu rę o f elcctrodo polarization in th e deposition o f m etals from solutions o f com plex salts. A nalysis o f th e cxpcrim ental resu lts o f S. Glasstono shows th a t th e eoneentration p olarization caused by oyanide aceum ulation a t tho cathode leads in m a n y cases to a rolation betw een polarization a n d eu rre n t d en sity sim ilar to tho eq u atio n for hydrogen overvoltage. T h is relatio n in th e case o f m ercury deposition from cyanidc solution indicates t h a t p olarization is o f a cliem ical n a tu rę a n d is induced by re ta rd e d diseharge o f th e ions in th e senso o f V olm er’s th eo ry o f overvoltage. N o definite conclusions can, how ever, bo d raw n from th e resu lts available for cadm ium a n d silver b u t in th o case o f copper th ey in d ieate t h a t no cliemical polarization, b u t ra th e r a depolarization effect, ta k e s place.— B. BI.The Hydrogen Film on a Polarized Metallic Electrode. G. Perfil’ev (Sot- zialist. Jiekonstruliziya i N a u ka , 1935, (3), 168; C. A bs., 1935, 29, 7826).— [In R ussian.] T he polarizatio n cap a c ity o f th e hydrogen film form ed on th e electrode in cathodic polarizatio n depends on th e d en sity a n d freąuency o f tho a.c. T he dependence o f tho ca p a c ity o f th e m ercury eathodo on tho p o te n tia l is expressed b y a curve w ith a sh a rp ly m ark ed m axim um . Tho hydrogen overvoltage dim inishes w ith inerease in th e cap acity a n d th e dim in u tio n o f the active resistance o f th e p olarization condenser u n d e r tho influence o f th e a.c.
—S. G.
V III.— R E F IN IN G
*Bullion Parting a t the H om estake Mine. N ath an ie l H erz (M in . and M et., 1935, 16, 500-504).—T he crudc m e ta l b ars ob tain ed in th e ex tra e tio n o f tho precious m etals from tho ore b y cyaniding a n d am alg am atio n contain gold 7 3 - 82, silver 17-5-23, copper 0-5-3, lead 0-5-1-5, iron 0-0-05, a n d a n tim o n y 0-0-5% . T he b ars aro m elted in a sm ali furnaco a n d th e m e ta l tra n sfe rre d to elay p o ts brasąu ed w ith b o ra x ; a ste a d y stre a m o f chlorine is bubbled th ro u g h th e m olten m etal to con v ert all th e baso m etals a n d th e silver in to cldorides leaving gold p u re r th a n 99-4%. T he slag is m elted w ith b o rax a n d a littlo soda ash to recover som c o f th e silver a n d a n y suspended gold, whilo leaving m ost o f tho silver chlorido u n a tta c k c d ; th is m etal is re tu rn e d to tho gold refining p o ts. Tho residual silver chloride is broken u p an d reduced to m etal w ith iron a n d sulpkuric acid, copper is e x tra c te d b y digesting th e sponge w ith hydrochlorie acid, a n d th e purificd spongo is m elted w ith b o rax an d soda ash to give p u re silver.—A. B . P.
IX .— ANALYSIS
Contribution to Applied Spectroscopy in Metal W orking Laboratories. I . - The Spectrographic A pparatus o£ the M.A.N. G. H eid h au scn (M itt. Forsch.
A n st. O .H .H .-K onzern, 1 9 3 5 ,4,59-70).—T he spectrographic o u tfit of a G erm an steelw orks la b o rato ry is deseribed w ith reference to illu stratio n s an d wiring diagram s, a n d som e exam ples o f its value in tho an aly sis o f Steel a n d cast iron aro given.—A. R . P.
p-H om osalicylic Aldoxime as a R eagent for Copper. C. H . K ao and K . H . Chen (J. Chinese Chem. Soc., 1935, 3, (1), 22-26).— [I n E nglish.] The rea g e n t solution is p rep ared b y d ilu tin g a n alcoliolie solution o f tho oxim e w ith w ater, an d filtering. Cu is p re c ip ita te d in tho prcsence o f aeetie acid a n d sodium a cetate, th e p recip itate containing 17-48% Cu. N i is ą u a n ti- ta tiv e ly p recip itated from n e u tra l solutions : tho p recip itatio n o f Co is incom- plete. M ethods o f sep aratin g Cu from E e '" , N i, a n d o th e r m etals, an d o f N i from Cd, Mg, a n d Al are sh o rtly deseribed.—P . M. C. R .
