Metallurgical Abstracts : general and non-ferrous, Vol. 1, Part 2

METALLURGICAL A B S T R A C T S

* (G ENERAL A N D N O N -F E R R O U S )

---

V o lu m e 1 F E B R U A R Y 1 9 3 4 P a r t 2

•»-“trat

■u

I — P R O P E R T I E S O F M E T A L S

(Continued from pp. 2—6.)

A lu m in iu m : R esistan ce to C o rro s io n a n d U se o f th e M e ta l in th e C hem ical In d u s try . Am. Matagrin (Rev. Chim. In d ., 1933, 42 , 66-72, 99-102, 128-

132).—A review, discussing corrosion-resistance, foundry practice, r o l l i n g ,

soldering, drawing, uses in the dairy, brewing, rubber and chemical industries’

and protection by anodic oxidation.-—E. S. H.

fH a s A lu m in iu m a T ra n s fo rm a tio n P o in t P 0. Tiedemann (Metallwirt- schaft, 1933, 12, 669-671).—T. has previously described (see J . h ist. Metals, 1926, 3 5 , 540) phenomena in aluminium which point to the existence of a transformation point; up to the present no satisfactory explanation of these has been advanced, nor have they been contradicted. The fact that the temperature curve for a number of properties shows no inflection is no indica­

tion of the absence of a transformation. The literature on transformations in zinc and cadmium is discussed.,—v. G.

fO n In v e s tig a tio n s o f th e A lle g e d A llo tr o p y o f A lu m in iu m . A. Schulze (Metallwirtschaft, 1933, 12, 667-669).—A review of articles published on this subject to date leads to the conclusion that aluminium has no transformation point and that observed irregularities in the temperature curves of various properties are due to the effects of impurities.—v. G.

A m o rp h o u s -C ry s ta llin e T ra n s fo rm a tio n o f A rs e n ic an d A n tim o n y . G. R.

. Levi and D . Ghiron

(Atti

R . Accad. Lincei Rend., 1933, [vi], 17, 565-569;

Chem. Zentr., 1933, 104, I I , 3082).—The conversion of amorphous antimony into the crystalline form is accelerated by such catalysts as hydrochloric acid and hydriodie acid; there is no definite transformation temperature, but the change can occur at 180° C., although 270° C. was previously thought to be the minimum temperature. Reduction of antimony chloride to metal invariably yields the amorphous form, whereas reduction of other salts in the absence of chlorides yields the crystalline form. Rapid heating of the amorphous form causes the change to occur explosively, but explosion may be avoided by prolonged heating at low temperatures.—A. R. P.

*O n a P o ly m o rp h ic T ra n s fo rm a tio n o f C a lc iu m . A. Schulze and H. Schulte- Overberg (Metallwirtschaft, 1933, 1 2, 633-635).—Thermal, electrical, and dilatometric tests on calcium containing 4-6% of impurities, including carbon, oxygen, a trace of iron, and 1-7% nitrogen, indicate the existence of a trans­

formation at 430°^450° C. accompanied by a heat evolution of 2-3 -4- 0-3 cal./grm.—v. G.

* X -R a y In v e s tig a tio n s o n C a lc iu m a t H ig h T e m p e ra tu re s . L. Graf (Metallwirtschaft, 1933, 1 2, 649-653).—X-ray examination of the calcium used by Schulze and Schulte-Overberg (cf. preceding abstract) showed that the metal is face-centred cubic at low temperatures (a= 5-56 A. at 20° C.) and body-centred cubic above 450° C. (a= 4-43 A. at 480° C.). The re­

crystallization temperature of cold-worked calcium is about 350° C.—v. G.

^M e a su re m e n ts o n C o n ta c t P o te n tia l D iffe re n c e b e tw een D iffe r e n t Faces o f Copper S in g le C rysta ls. Bernhard A. Rose (Phys. Rev., 1933, [ii], 4 4 , 585- 588) Cf. J. Inst. Metals, 1933, 5 3 , 482. The contact p.d. between (111)

* D e n o te s a p a p er d e s c r ib in g t h e r e s u lts o f o r ig in a l resea rch , f D e n o te s a fir s t-c la s s c r itic a l r e v ie w .

F

6 6

Metallurgical Abstracts

V o l . 1 a n d (100) faces of single c ry sta ls of co p p er h a s b een m ea su re d a t d iffere n t stages of a th o ro u g h o utgassing tre a tm e n t. T h e first effect of o u tg a s sin g is to reduce th e surface gas la y e r to a th ic k n e ss a t w h ich i t h a s a d efin ite crystal s tru c tu re r e la te d to t h a t of th e u n d e rly in g co p p er. A lth o u g h fu rth er tre a tm e n t rem oves th e re sid u al gas, i t also p ro d u c es new c r y s ta l facets by e v ap o ra tio n of copper, so t h a t a tr u e final s ta te c a n n o t b e o b ta in e d . The re s u lts in d ic a te t h a t th e c o n ta c t p .d . b etw ee n th e ab o v e tw o faces is a t least 0-384 v ., a n d is p ro b a b ly g re a te r t h a n 0-463 v. T hese v a lu e s a re m u c h greater t h a n was ex p ected for a sy m m etric a l cubic c ry s ta l. F o r p o ly c ry s ta llin e copper th e c o n ta c t p.d. betw een th e p la te s falls to o n ly 0-01 v . a f te r outgassing.

— W . H .-R . The F o rm a tio n o f O xide F ilm s o n G old a n d Ir o n . W illia m J a m e s S h u tt a n d A rth u r W alto n [Trans. Faraday Soc., 1933, 2 9 , 1209-1216).—The p assiv atio n of gold b y tr e a tm e n t w ith a lk a lis is e x p la in ed , o n th e b asis of the oxide film th e o ry of p a ssiv ity , b y th e in te ra c tio n of t h e g old w ith th e solution to fo rm a lay e r of gold oxide w h ich c an be re n d e re d f u lly p assiv e by sub­

seq u e n t anodic tre a tm e n t. T h e chem ical re a c tio n b y w h ic h th e oxide film is fo rm ed re s u lts in th e lib e ra tio n of h y d ro g e n w h ic h is a d so rb e d on th e gold ; w hen th e p a ssiv a te d m e ta l is tr e a te d w ith d ilu te h y d ro c h lo ric a c id , th e oxide film dissolves, b u t th e h y d ro g e n re m a in s ad so rb ed a n d , if sufficient is present, p re v e n ts f u r th e r a c tio n of a lk a lis. I f o x idizing a g e n ts , su c h a s hypochlorite, a re a d d e d to so lu tio n s in w h ic h th e ox id e film is fo rm ed , no hydrogen is ad so rb ed , a n d th e loss in w e ig h t o n tr e a tin g t h e p assiv e m e ta l w ith hydro­

chloric a cid corresponds closely w ith t h a t e x p e c te d b y t h e fo rm atio n of a m onom olecular la y e r of g old oxide. N o film c a n b e d e te c te d in solutions of low h y d ro x y l-io n c o n c e n tra tio n c o n ta in in g o x id izin g a g e n ts , su c h as con­

c e n tra te d n itric a c id o r acidified p e rm a n g a n a te so lu tio n , p ro b a b ly owing to th e rem o v al of a d so rb ed h y d ro g e n a n d th e slow ness of th e form ation of gold oxide. I n a c id so lu tio n s th e p o te n tia l of a n e le ctro d e containing ad so rb ed h y d ro g e n fa lls w ith in creasin g pa m ore ra p id ly t h a n t h a t of an electro d e fro m w h ich th e h y d ro g e n h as b een re m o v e d b y chlorine, b u t in alk a lin e so lu tio n th e p o te n tia ls a re th e sam e, since m ore a d so rb e d hydrogen is re a d ily p ro d u ced .— A. R . P .

* S tu d y o f th e E le c tric a l P ro p e rtie s o f T h in Films o f P la tin u m O btained by C a th o d ic P u lv e riz a tio n in S im p le Gases. A n d ré F é r y (./. Phys. Radium, 1933, [vii], 4, 301-315).— F ilm s of p la tin u m fo rm e d b y cath o d ic discharge in h eliu m , oxygen, n itro g e n , a n d h y d ro g e n a re n o t c h a ra c te riz e d b y definite p ro p e rties . T h ey ab so rb th e gas p re s e n t in th e d isc h arg e tu b e . A t room te m p e ra tu re th e e le ctrica l re sista n c e of t h e film s d im in ish es a f te r th e ir form a­

tio n ; i t decreases f u r th e r on h e a tin g , a n d gas is ev o lv ed sim ultaneously.

O rd in a ry p la tin u m is n o t o b ta in e d e v e n a f te r h e a tin g a t 50 0 ° C.— E . S. H.

* O n th e N a tu re o f th e S po n ta n e o u s S e p a ra tio n o f P o lo n iu m on S ilve r in V a rio u s A c id s . O tto E rb a c h e r (Z. physikal. Chem., 1933, [A], 165, 421-426).—

T h e p h en o m en a a sso c iated w ith th e sp o n ta n e o u s s e p a ra tio n of polonium on silv er c an be ex p la in ed b y th e follow ing tw o a s su m p tio n s : [a) a n electro­

ch em ical ex ch an g e of th e silv er a to m s w ith th e m ore n oble polonium ions, (b) fo rm atio n of a solid so lu tio n of p o lo n iu m in th e silv er p ero x id e film produced b y th e ozone fo rm ed b y t h e a c tio n of t h e a -ra y s e m itte d fro m th e polonium .

— B. Bl.

Som e P ro p e rtie s a n d Uses o f R h e n iu m (D v i-M a n g a n e s e ). J . G. F . Druce (Indust. Chemist, 1933, 9 , 244).— A rev iew of p u b lis h e d w o rk .— E . S. H .

T h e A to m ic M ass o f S o d iu m . I I . — T h e S o d iu m C h lo rid e -S ilv e r R atio.

C lyde R . J o h n s o n (J. Phys. Chem., 1933, 3 7 , 923-933).— F iv e d eterm inations of th e so d iu m c h lo rid e : silv e r ch lo rid e r a tio g a v e t h e v a lu e 22-994 for the ato m ic m ass of so d iu m .— J . S. G. T .

» M e ch a n ica l P ro p e rtie s o f E le c tr o ly tic Z in c Sheets. 0 . B au er a n d J . finite, W eerts [w ith F . B eck]

(Metallwirtschaft,

1933, 12, 615-618).— T ensile and

bending te s ts h a v e been m ad e o n v a rio u s ty p e s of zinc sh e e t a t tem p er- tilt'.: a tu res betw een — 80° C. a n d + 220° C. T h e sh e ets a re an iso tro p ic, th e :c . tensile s tre n g th in th e d irec tio n of ro llin g being a b o u t 10% less, a n d th e tejj elongation a n d ben d in g s tre n g th a b o u t 3 0 -5 0 % g re a te r th a n in th e tran sv erse a*.'. direction. T h e elo n g atio n falls ra p id ly below 20° C. a n d th e ben d in g s tre n g th

% below 40° C. U p to 0-06% of im p u rity (lead, iro n , copper, cadm ium ) found in com m ercial e le ctro ly tic zinc h av e no a p p rec ia b le effect on th e m echanical pro p erties of h o t-ro lle d sh e e t. A g ra d e of zinc w ith 0-9% le a d show ed a tensile s tre n g th a b o u t 2 5 % g re a te r t h a n t h a t of e le ctro ly tic zinc, b u t th e e longation a n d ben d in g s tre n g th w ere m u ch lo w e r; th e effect of te m p e ra tu re on th is m a te ria l w as sim ilar to t h a t on th e o th e r g rad es of zinc te s te d .— v. G.

-[Im p u ritie s in C o m m e rc ia l Z in c . W e rn e r F rö h lic h

(Met. Ind. (Land.),

1933, 43, 559—560, 589—590).— T h e chief im p u ritie s in co m m ercial b ra n d s of p rim a ry zinc a re cad m iu m , lea d , a n d iro n , w h ilst tin , copper, a n tim o n y , arsenic, a n d a lu m in iu m m a y also be p re s e n t in re m e lte d zinc. C adm ium causes considerable in crease in h ard n ess, b rittle n e ss , a n d h o t sh o rtn e ss;

th e m ax im u m perm issible a m o u n t is 0-25% fo r ro llin g a n d 0 -1-0-75% for - galvanizing, acco rd in g to w h e th e r m u ch o r little b e n d in g is to be im posed.

C adm ium is som etim es a d d e d to im p ro v e th e flu id ity of th e b a th . L ead is re la tiv e ly harm less, a n d te n d s to increase th e so ftn ess a n d d u c tility of coatings a n d to n e u tra liz e th e effect of c a d m iu m ; ro llin g zinc m a y c o n ta in 1-25 a n d is: galvanizing zinc 0 -3 -0 -5 % . I t also increases th e w e a th e rin g re sistan ce of

zinc. M ore th a n 0-015% of iro n m ak e s zinc to o h a rd a n d b r ittle fo r ro llin g ; large a m o u n ts in crease th e a m o u n t of dross a n d a sh e s in th e g alvanizing b a th a n d low er th e a cid co rro sio n -resistan ce of zinc. T in is ra re ly p re sen t, b u t u p to 0-75% te n d s to p ro d u ce b rig h te r a n d sm o o th er c oatings. R o llin g zinc sh o u ld n o t c o n ta in m ore th a n 0-15% of co p p er a n d galv an izin g zinc n o t m ore th a n 0-2% , la rg e r a m o u n ts in th e l a t t e r c ausing a yellow sheen.

All k in d s of zinc sh o u ld c o n ta in as lit t le a rsen ic a n d a n tim o n y as possible (not m ore th a n 0 -1% ), a n d g a lv an izin g zinc n o t m ore t h a n 0 -0 1 % of alu m in iu m .— J . H . W .

Creep of M e ta ls . J . N e ill G reenw ood (

Modem Eng.,

1933, 7, 322-324).—

A brief su rv e y of creep p h e n o m e n a a n d t h e ir in v e s tig a tio n .— H . W . G. H . M o d e m R esearches o n th e P ro p e rtie s o f E n g in e e rin g M a te ria ls . J . N eill G reenw ood (

Modem Eng.,

1933, 7, 243-2 4 8 a n d 2 7 7 -2 8 1 ).— A re v iew of p re sen t know ledge of th e fa tig u e , co rro sio n -fatig u e, a n d creep p ro p e rties of m aterials, ste els in p a rtic u la r, is follow ed b y a d iscussion of its a p p lic atio n to th e p ro b lem of design. R e fere n ce is m ad e p rin c ip a lly to th e w ork of Gough, H aig h , a n d M cA dam .— H . W . G. H .

T h e rm a l E ffe c ts in E la s tic a n d P la s tic D e fo rm a tio n . M. F . S a y re

(Proc.

Amer. Soc. Test. Mat.,

^{1932, 3 2 ,} ( II), 5 8 4 -5 9 2 ; d iscussion, 593-606).— See

J. Inst. Metals,

1932, 5 9 , 468. T h e discussion, in w h ic h

A. Nadai, L. B.

Tuckerman,

a n d

M. F. Sayre

to o k p a r t, deals chiefly w ith th e te s tin g of steel proving rin g s fo r th e rm a l cree p .— A. R . P .

E la s tic ity , P la s tic ity , T o u g h n e ss, B rittle n e s s , a n d H a rd n e ss. M. R o s a n d A. E ich in g er

(Assoc. Internat. Essai Mat., Congres de Zürich,

1932, (II), 530-543).— [ I n G erm an .] See

J. Inst. Metals,

1931, 47, 473.— S. G.

R e la tio n s be tw een E la s tic ity a n d P la s tic ity , T o ugh ness a n d B rittle n e s s . P ra c tic a l M eans o f C h a ra c te riz in g T h e m . P . R e g n a u ld

(Assoc. Internat.

;

Essai Mat., Congres de Zürich,

1932, ( II), 544 -5 4 7 ).— [ I n F re n c h .] See

J.

,i

Inst. Metals,

1931, 47, 473.— S. G.

E la s tic ity a n d P la s tic ity , T e n a c ity a n d F r a g ility . G. S achs

(Assoc. Internat.

Essai Mat., Congres de Zürich,

^1932, (II), 54 8 -5 5 4 ).— [ I n G erm an .] See

J.

Inst. Metals,

1931, 47, 473.— S. G.

1934

I . — Properties o f Metals 67

68

68 Metallurgical Abstracts

^{Vo l. 1}

I c T O l * 1 / O . V J . .

On th e R e la tio n E x is tin g betw een E la s tic ity , P la s tic ity , T e n a c ity , and B rittle n e ss . S uggestion in R ega rd to a M e a s u re m e n t f o r T e n a c ity un der a S tatic L o a d P h . T heodorides

(Assoc.

P it m a t .

Essai

M at.,

tongres de Zurich,

1932, (II), 5 6 7-5 7 0).— [In G erm an.] S ta n d a rd d efinitions of th e te rm s elasticity, p las tic ity , te n a c ity , a n d b rittlen e ss are suggested a n d d iscu ssed . I t is pro­

posed t h a t th e d e te rm in a tio n of elastic lim it be re p la c e d b y t h e determ in atio n of th e low er lim it of p la s tic ity . T e n a c ity sh o u ld be defin ed as th e capacity of a m a te ria l fo r p lastic d e fo rm a tio n u n d e r in cre a sin g fo rce s a n d sh o u ld be m easu red b y d e te rm in in g th e ra tio of tw o w o rk -v alu es u n d e r a s ta tic load.

— A. R . P.

D iscussion [o n E la s tic ity , P la s tic ity , & c .] M. S p in d el. W . R u tg ers. J.

B a sta. M. R o s. P . S an to R in i. W . R o se n h a in . H . F ro m m . H . Rabozee.

A. M esnager. W . T afel

(Assoc. Internat. Essai Mat., Congres de Zurich,

1932, (IIjT 574—584).— [In E n g lish , F re n c h , o r G erm an .] T h e discussion deals w ith th e n ece ssity of sta n d a rd iz in g t h e m e th o d s of d e te rm in in g the vario u s p la s tic a n d ela stic p ro p e rties of m e ta ls a n d w ith th e n e ed for inter­

n a tio n a lly a ccep ted d efinitions of th e s e p ro p e rtie s .— A. R . P .

R e m a rk s on a T h e o re m o f C o n se rva tio n in th e T h e o ry o f M e ta ls . F. Bloch

(J. Phys. Radium,

1933, [vii], 4 , 486^491).— T h e o re tic a l.— E . S. H .

fM e ta llu r g ic a l P ro b le m s in H a n d lin g H y d ro g e n u n d e r H ig h Pressures and T e m p e ra tu re s . J o h n L . Cox

(Trans. Amer. Inst. Chem. Eng.,

^{1933, 29,}

43-87).— T h e first p a r t of th e p a p e r d iscusses p u b lis h e d w o rk on creep, p a rtic u la rly in re sp e c t of allo y ste e ls. R eferen ce is m ad e to th e a ctiv e effect of chrom ium in raisin g creep s tre n g th . A

bibliography,

c o n ta in in g references to 220 p a p ers on creep, in clu d in g n o n -ferro u s m e ta ls a n d allo y s, is given.

T he second p a r t review s p u b lish ed w o rk o n th e corrosion a n d e m b rittlin g of m eta ls a n d alloys (m ainly allo y steels) a t h ig h te m p e ra tu re s b y hydrogen.

♦R esearches on M e ta l E le c tric A rc s . T . T oniszew ski a n d T . Maciejewski

(Acta Phys. Polon.,

1933, 2, 6 7 -7 4 ).— T h e s ta tic c h a ra c te ris tic s of a rcs between p lan e a n d hem isp h erical m e ta l e le ctro d e s a re g iv en fo r a ll possible com­

b in atio n s of iro n , copper, m o ly b d e n u m , tu n g s te n , a n d b rass. T he Ayrton c o n sta n ts of th e sy ste m s c o p p e r-c o p p e r, m o ly b d e n u m -m o ly b d en u m , and tu n g s te n -tu n g s te n h av e been d e te r m in e d ; w ith th e second p a ir these co n sta n ts a re th e sam e fo r a ll c u rre n t d e n sitie s, w h ereas w ith th e o th e r pairs th e re a re tw o c u rre n t-d e n s ity ra n g es w h e rein th e s e c o n s ta n ts v a ry .— A. R. P.

* T h e o ry o f th e D ependence o f th e E le c tr ic a l C o n d u c tiv ity o f M etals on P ressure. W olfgang K ro ll

(Z. Physik,

1933, 85 , 398-4-02).— T he effect of p ressu re on th e ele c trica l c o n d u c tiv ity of m e ta ls is d iscu ssed along th e lines of B lo ch ’s th eo ry . T h e effect is c o rre c tly in te r p r e te d if F e rm i’s expression for th e p o te n tia l a t a la ttic e p o in t is u se d in th e th e o ry .— J . S. G. T.

♦ M a g n e tic In te r a c tio n o f M e ta llic E le c tro n s . C ritic is m o f F r e n k e l’ s Th eory of S u p e r-C o n d u c tiv ity . H . B e th e a n d H . F rö h lic h

(Z. Physik,

^{1933, 85, 389—}

397).— F re n k e l’s th e o ry of s u p e r-co n d u c tio n , a ttr ib u tin g th e phenom enon to m ag n etic forces called in to p la y b e tw ee n th e e le ctro n s, is considered to be u n te n a b le . Such forces, i t is show n, c a n in no w a y affect th e value of the c o n d u c tiv ity , a n d a re re v ealed , m ac ro sc o p ic a lly o n ly , in th e phenom enon of se lf-in d u ctio n . T h e w o rk is e n tire ly m a th e m a tic a l in c h a ra c te r.— J . S. G. T.

— E . S. H.

1934

I I . — Properties o f Alloys 69

I I . — P R O P E R T I E S O F A L L O Y S (Continued from pp. 7-11.)

♦Studies o i th e T e rn a ry S ystem A lu m in iu m - A n tim o n y - M a g n e s iu m . W . G uertler a n d A. B erg m an n

(Light Metals Research,

1933, 2, (39), 1-14).—

A full, illu s tra te d tra n s la tio n fro m

Z. Metallkunde,

^{1933, 25, 81, 111. See}

J .

Inst. Metals,

^{1933, 53,} 343.— J . C. C.

♦ T h e rm a l M e a su re m e n ts on H a rd e n a b le A lu m in iu m A llo y s . W . F raen k el (

Metallwirtschaft

, 1933, 1 2 , 583-585).— H e a tin g c u rv es hav e b een ta k e n b y a sensitive d ifferen tial m eth o d on alu m in iu m allo y s w ith

(a)

4 % copper,

(b)

^{4 %}

copper a n d 0-5% m agnesium , a n d (c) 4 % copper, 0-5% m agnesium , a n d 0-5%

m anganese. I n a ll cases a n a b so rp tio n of h e a t o ccurs before tr u e p re c ip ita tio n com m ences, a n d p re c ip ita tio n its e lf is a cco m p an ied b y a n e v o lu tio n of h e a t w hich for q u e n ch e d a n d a g ed specim ens is as g re a t as, o r g re a te r th a n , t h a t for fresh ly q u en ch ed specim ens. A geing is th ere fo re n o t asso ciated w ith p re cip ita tio n .— v. G.

♦ H e a t E v o lu tio n a n d M e c h a n is m o f T r a n s fo rm a tio n o f H a rd e n a b le A lu m in iu m A llo y s . H . R ö h rig

(Metallwirtschaft,

1933, 12, 671).— Cf.

preceding a b s tra c t. I n th is c o n n ectio n a tte n tio n is d irec te d to th e w o rk of K okubo a n d H o n d a

(J. Inst. Metals,

1931, 47, 266) in w h ich sim ilar re su lts were o b tain e d .— v. 6 .

O n th e M e c h a n ic a l a n d C h e m ic a l P ro p e rtie s o f A llo y s o f A lu m in iu m w ith Cr, Fe, M g , M n , T i, V . H . B o h n e r

(Light Metals Research,

1933, 2, (29), 1 - 2 3; a n d

Met. Ind.

(

Lond

.), 1933, 43, 2 7 -3 0 , 56 -5 8 ).— T ra n s la te d in fu ll from

Metallwirtschaft,

^{1933, 12,} 251-255, 265-267. See

J. Inst. Metals,

^{1933, 53,}

694.— J . C. C.

♦T he “ P re c ip ita tio n H e a t-T r e a tm e n t ” E ffe c ts in C o p p e r- A lu m in iu m A llo y s . W . S tenzel a n d J . W e e rts

(Light Metals Research,

1933, 2, (37), 2 -2 5 ).— A full tran s la tio n , illu s tr a te d b y sk e tch es, fro m

Metallwirtschaft,

1933, 12, 353, 369. See

J. Inst. Metals,

^{1933, 53,} 694.— J . C. C.

tN ic k e l in th e L ig h t A llo y s . J . C o u rn o t

(Rev. Nickel,

1933, 4, 137-142).—•

Of th ese alloys D u ra lu m in is th e o ld e st a n d th e m o d ern process of p re cip ita tio n - h ard en in g h as b ro u g h t its use to a b e tte r u n d e rsta n d in g . I t is, how ever, corrodible. A d d itio n of 2 % cad m iu m , a n d th e ju x ta p o s itio n of a lu m in iu m an d D u ralu m in sh eets h av e been su g g ested as rem edies in c e rta in special alloys.

U sually, how ever, th e s e m a te ria ls re q u ire d e lic ate h a n d lin g . In c re a sin g th e q u a n tity of nick el in th is ty p e of a llo y gives a fine s tr u c tu r e a n d b e tte r p h y s ­ ical p ro p erties. A d d itio n of sm all q u a n titie s of c h ro m iu m reinforces th e effect of nickel, giving m a te ria l possessing h o m o g en eity , s ta b ility , a n d in o x id iz ­ ab ility .— W . A. C. N.

T h e A lu m in iu m A llo y A n tic o r o d a l. A. I . A . G.

(Schweiz. Tech. Z.,

^1933,

236-239).— A n tico ro d al is u sed e x clu siv ely fo r d e c o ra tiv e w ork. I t s p h y sical p ro p erties are ta b u la te d . Som e of its m a n y a p p lic a tio n s are illu s tra te d .— W . N.

♦ T h e S ystem I r o n - C o b a lt - A lu m in iu m . W e rn e r K ö s te r

(Arch. Eisen­

hüttenwesen,

^{1933, 7,} 263 -2 6 4 ).—T h e space m o d el of th e solid s ta te of ir o n - c o b alt-a lu m in iu m allo y s differs fro m t h a t of t h e co rresp o n d in g m e ta l sy stem (see K o s te r,

Met. Abs.,

th is v o l., p. 71) o n ly in th e size of th e v a rio u s fie ld s ; th is is d u e to th e s im ila rity in t h e n ic k e l-a lu m in iu m a n d c o b a lt-a lu m in iu m system s. O b serv atio n s on th e m a g n e tic tra n s fo rm a tio n h a v e afforded sim ilar, as y e t u n ex p lain ed , re s u lts to th o se o b serv ed in th e n ick e l sy s te m .— J . W .

♦T h e S ystem Iro n -C o b a lt-M a n g a n e s e . W e rn e r K ö s te r a n d W in fried S chm idt

(Arch. Eisenhüttenwesen,

1933, 7, 121-126).— T h e y -e b o u n d a ry in th e c o b a lt-m a n g a n e se sy s te m h a s been e sta b lis h e d a n d th e v a ria tio n of th e la ttic e c o n s ta n ts of th e tw o p h a se s w ith th e co m p o sitio n d e te rm in e d . The te m p e ra tu re of th e y - e tra n s fo rm a tio n a n d of th e m ag n e tic tra n s fo rm a tio n of co b alt a re so q u ick ly re d u c e d b y a d d itio n of m an g a n ese t h a t th e y re ac h

70 Metallurgical Abstracts

^{Vo l. 1}

room te m p e ra tu re a t 30% a n d 38% m an g an ese, re sp e c tiv e ly . T h e tern a ry sy stem iro n -co b a lt-m an g a n e s e u p to 5 0 % m an g a n ese h a s b e e n stu d ie d by d ilato m etric, X -ray , a n d m icrographie m eth o d s. B elow 1400 C. hom ogeneous y is form ed w hich is co n v erted a t low er te m p e ra tu re s to a in allo y s containing u p to 18% m anganese a n d 8 0 % co b alt. T h e degree of h y ste res is of this re actio n increases w ith increase in th e m an g an ese c o n te n t. B etw een 18 a n d 30% m anganese th e y-phase is co n v erted p a r tly o r w h o lly in to e. The y—e tra n sfo rm a tio n in th e iro n —m anganese sy ste m is co m p le te ly analogous to th e corresponding tra n s fo rm a tio n in p u re c o b a lt a n d in t h e te r n a r y system th ese tran sfo rm a tio n s a re jo in ed to g e th e r b y a p lan e of eq u ilib riu m . W ith a c o n sta n t m anganese c o n te n t th e la ttic e p a ra m e te rs of th e te r n a r y y- and e-phases decrease, a t first lin early , th e n m ore ra p id ly a s t h e iro n is replaced b y co b alt ; w ith a c o n sta n t iro n o r c o b a lt c o n te n t, h o w ev er, th e y increase lin early w ith increasing m anganese c o n te n t. T h e c h an g e fro m th e ferro- to th e para-m ag n e tic s ta te does n o t a p p rec ia b ly affect th e dep en d en ce of the p a ram ete rs on th e c o n ce n tra tio n , b u t th e la ttic e of th e ferro m a g n etic phases a re larg e r th a n those of th e p a ram ag n e tic .— J . W .

A N e w C o rro s io n -R e s is ta n t Copper A llo y . [C o r r ix .j A non. (Metallwirt- schaft, 1933, 12, 622).— C orrix is a n a llo y of c o p p er 86, alu m in iu m 10, and iro n 4 % m ad e from sp ec ia lly p u rified m eta ls. I t c an b e c a s t a n d worked read ily , a n d to w ard s m an y re ag e n ts is as r e s is ta n t to co rro sio n as th e austenitic c h ro m iu m -n ick el steels.— v. G.

Copper A llo y s th a t H a v e th e S tre n g th o f Steel. A n o n . (M achinery (N .Y.), 1933, 40, 104—105).— T he c h a ra cte ris tic s a n d uses of s ilic o n -b ro n ze a n d beryl­

liu m -c o p p er alloys are briefly review ed.— J . C. C.

fT h e A lu m in iu m - “ B ro n z e s .” E . C. J . M a rsh a n d E . M ills (Aircraft Eng., 1933, 5, 251-255, 286-288).— A g e n eral s u rv e y of th e s u b je c t w ith reference to th e u su al com m ercial form s, m eth o d s of m a n u fa c tu re , w o rk in g properties, h e a t-tre a tm e n t, m ic ro -stru c tu re , co rro sio n -resistan ce , &c.— H . S.

In v e s tig a tio n on th e T ra n s fo rm a tio n s i n th e S o lid S tate in th e System Copper- G old. G iin ter W eh n er (Thesis: Univ. Leipzig, 1931, 78 p p .).— See J . Inst.

Metals, 1932, 50, 730.— I . M.

* T h e M o d u lu s o f E la s tic ity o f A n n e a le d a -B ro n z e s . L éo n G uillet, Jr.

(Compt. rend., 1933, 197, 1320-1321).— T h e k in d of e la stic deform ation im posed on a bod y is im p o rta n t. T o rsio n a n d b e n d in g a re heterogeneous d eform ations. O n th e o th e r h a n d , if th e te s t-p ie c e is long re la tiv e to its cross-sectional a rea, th e stre ss im posed b y te n s io n is th e sam e in a ll p a rts of th e section, i.e. th e d e fo rm a tio n is hom ogeneous ; i t is, how ever, relatively v ery sm all, a n d p u re ten s io n is difficult to a p p ly . E lo n g a tio n s have been m easured to m m . w ith a M a rte n s’ e la stic im e te r, lo ad s of a b o u t 30 grm ./

m m .2 being a p p lie d w ith a n A m sle r m ac h in e w ith t h e h e lp of wedges, a t c o n sta n t speed w ith in cre asin g a n d d e cre asin g lo ad s. T h e v a lu e s of Young’s m odulus a re ta b u la te d below , a n d w ill be seen to d im in ish a s th e tin content increases in a n a p p ro x im a te ly lin e a r re la tio n s h ip . T h is agrees perfectly w ith C h ev en ard a n d P o rte v in ’s re s u lts fo r th e m o d u lu s of to rsio n of certain alloys (brass, c u p ro -n ic k e l, c o p p er, &c.) :

Tin, %. Copper, % . Young's Modulus,

Mean Value.

1-92 97-97 12,600

3-81 96-10 12,300

6-05 93-85 11,970

8-02 91-92 11,650

9-90 90-05 11,260

— J. H . W.

1934

I I . — Properties o f Alloys 71

Notes o n V o lv it B ro n z e . Anon. (

Metallwirtschaft,

1933, 12, 674).—Volvit bronze contains 9% tin and considerable amounts of phosphorus. By careful supervision of the casting and working operations, cold-rolled tubes and rods can be made of this alloy. I t has a Brinell hardness of 230 in the drawn state, whilst the annealed metal has a tensile strength of 40 kg./mm.2 and an elongation of 70%. The alloy is suitable for making all types of bearing boxes.—v. G.

in f lu e n c e o f T e m p e ra tu re o n th e M e c h a n ic a l P ro p e rtie s o f B rasses.— I . —II .

W. Broniewski and K. Wesołowski

(Rev. Met.,

1933, 30, 396—401, 453-457).—

[I.—] Tests included tensile tests on thin sheets (5 mm.) at elevated temper­

atures, thin sheets being chosen to obviate serious cooling of the test-length by conduction of heat to the testing-machine. Hardness tests were made at elevated temperatures, the ball and mounting used to determine the hardness being heated to temperature with the specimen. In making impact tests at elevated temperatures the test-piece was heated on the hammer itself.

Three brasses were used containing: (1) zinc 33%; (2) zinc 40%; and (3) zinc 40, lead T3%. The results of tests made at temperatures in the range

— 200° to 700° C. are given as graphs and are compared by B. and W. with the results of tests published by other investigators. [II.—] In brasses containing 33% of zinc the effect of cold-work is no longer observed in the mechanical properties above 400° C. In pure brasses of 40% zinc the effect of cold-work is more persistent, and does not disappear from the diagram of notched-bar values until 600° C. is exceeded. The introduction of lead into brass seems to lower that limit to about 500° C. For the three brasses studied, the curves of tensile strength, elastic limit, and hardness are of similar form, having a rapid descent at a fairly low temperature in the zone of recrystallization with ranges of less rapid change on each side.—H. S.

P .M .G . A llo y . Anon.

(Machinery (Lond.),

1933, 42, 770-771).—The properties in the cast and forged conditions of 18 copper alloys made up with P.M.G. hardener alloy in various proportions, with or without zinc, are tabulated. Some typical applications are quoted.—J. C. C.

T e llu riu m -L e a d . W. Singleton (

Plumbing Trade J.,

1934, 13, 242-243).—

A lecture to the Institute of Plumbers on the properties of tellurium-lead and its applicability to plumbing.—E. S. H.

*O n Z in c in L e a d B e a rin g M e ta ls . K. L. Ackermann

(Metallwirtschaft,

1933, 12, 618-619).—If there is sufficient antimony in lead-antimony-zinc alloys, the zinc forms a compound which crystallizes in long, brittle crystals which make the alloy hard but brittle. If tin is also present, it combines with part of the antimony, and some of the zinc is set free. Zinc produces difficulties in casting, especially when heavy metals such as copper, iron, and nickel, are also present, and must therefore be considered as an undesirable constituent of lead bearing metals.—v. G.

M e c h a n ic a l P ro p e rtie s o f W h ite - M e ta l B e a rin g A llo y s a t D iffe r e n t T e m ­ pe ra tu re s. H. K. Herschman and J. L. Basil

(Proc. Amer. Soc. Test. Mat.,

1932, 32, (II), 536-555; discussion, 556-557).—-See

J. Inst. Metals,

1932, 50,

429.—S. G.

*S tu d y o f th e U lt r a - L ig h t A llo y s o f M a g n e s iu m , A lu m in iu m , a n d Copper.— I .

Paul Bastien

(Rev. MR.,

1933, 30 , 478-501).—See

J. Inst. Metals,

1933, 53,

623.—H. S.

*T h e S ystem I r o n - N ic k e l- A lu m in iu m . Werner Koster

(Arch. Eisen-

hiittenwesen,

1933, 7, 257-262).—The system has been examined thermally and micrographically up to 30% aluminium. Since the compound NiAl forms a continuous series of solid solutions with a-iron within the range tested, the alloys contain only the a- and y-phases. The (a + y)-field is divided into 2 parts, the first forms a narrow wedge extending out from the scythe-shaped (a + y)-field of the iron-aluminium system, and the second a broader wedge

72 Metallurgical Abstracts

^{Vo l. 1}

extending to room temperature from the nickel-ahiminium system down to a very low nickel content and broadening with decreasing temperature.

The magnetic transformation point of iron-aluminium alloys is first raised by addition of nickel; for alloys with a high content of nickel and aluminium, however, it occurs at a considerably lower temperature after quenching from a high temperature than after cooling slowly from a medium temperature.

The a-phase is ferromagnetic up to a content of 70% nickel and about 20%

aluminium.—J. W.

Stainless N ic k e l C h ro m iu m A llo y . [In c o n e l.] Anon. (

Indust. Australian,

1933, 88, 269).—See J . Inst. Metals, 1933, 53, 437.—P. M. C. R.

tC h r o m iu m - N ic k e l as a C o rro s io n -R e s is ta n t A llo y . Robert J. McKay (Metals and Alloys, 1933, 4, 177-180, 202-204).—A review of the properties, uses, and resistance to corrosion of nickel-chromium alloys, especially Inconel (chromium 12-14, iron 5-6%, remainder nickel).—A. R. P.

C h ro m iu m -N ic k e l R esistance A llo y s . Anon. (Arch. tech.

Messen,

1933,

3, (29), f30).—An account of certain proprietary resistance alloys, including Megapyr. Their analyses and physical properties are tabulated, and per­

missible working temperatures and special applications are indicated.—P. R.

S ym p o siu m on E le c tric R e sistan ce A llo y s . Anon.

(Japan Nickel Rev.,

1933, 1, 376).—[In English and Japanese.] A very brief summary of the proceedings.—W. A. C. N.

R esistance A llo y s fo r H e a tin g , a n d T h e ir T e s tin g . W. Hessenbruch

(Arch,

tech. Messen, 1933, 3, (29), t155- t156).—The analyses, relevant physical properties, and approximate working ranges of a number of resistance alloys are tabulated, and comparative curves show the effect of temperature on the specific resistance of typical alloys. Mechanical properties at room tem­

perature are quoted, and curves show the limits of creep of certain materials at high temperatures. Methods of durability testing are discussed, and the influence of temperature on durability is shown graphically. The importance of surface loading, frequency and duration of run, furnace atmosphere, and of certain constituents of specific alloys are briefly discussed, results being tabulated in some cases.—P. M. C. R.

* A n In v e s tig a tio n o n th e N ic k e l-C h r o m iu m A llo y s . Yonosuke Matsunaga (Japan Nickel Rev., 1933, 1, 347-363).—[In English and Japanese.]

Specimens were melted in an hydrogen atmosphere in an electric furnace.

The specimens for thermal analysis were heated in hydrogen in thick-walled quartz tubes. For samples containing more than 70% chromium, however, interpolation methods had to be employed. Variations in solid solubility were traced by microscopic study. A new equilibrium diagram has been developed. A eutectic containing 51% chromium is formed at 1346° C.

The a-phase is soluble to the extent of 47% copper at 1346° C. and 44%

copper at room temperature. The corresponding figures for the [1-phase are 37 and 7% nickel respectively. Oxidation, hardness, and electric resis­

tivity measurements indicate that alloys containing 15-35% copper are best for heat-resistivity purposes. In any case, the chromium should be less than 50% of the alloy.—W. A. C. N.

E q u ilib r iu m D ia g ra m o f N ic k e l a n d C h ro m iu m . S. Nishigori and M.

Hamazumi (Japan Nickel Rev., 1933, 1, 391).—[In English and Japanese.]

Abstracted from Sci. Rep. Tohoku Im p . Univ., 1929, [i], 18, 491-502. See J . In s t Metals,1930, 43, 477.—W. A. C. N.

S tu d y o f th e L ife o f E le c tr ic H e a tin g W ire s . M. Horioka

(Japan

Nickel Rev., 1933, 1, 292-310).—[In English and Japanese.] An investiga­

tion of various methods for conducting forced life tests on resistance wires for electric heating. In ideal tests of this nature the following factors would be altered simultaneously—oxidation, protection by oxide film, change of internal structure, heterogeneity of material, and strength at high tempera-

1934

I I . — Properties o f Alloys

7 3 ture. As this, however, cannot be done easily the tests preferred were_

forced oxidation test in oxygen, measurement of oxidation by thermo-balance, measurement of the weight of oxidized matter peeled off from the surface, brine test, microscopic study, measurement of cracking and peeling-off sound in the cooling. The experimental results are given in tabular and graphical form. It is stated that there is a definite relation between the life of resistance wire and the absolute temperature at which the wire is put into service.

The breakdown hrs. in air can be lengthened by 4 or 5 times when the running temp, is lowered by 100° C. in the range between 800° and 1300° C.

The breakdown of wires tested in air frequently occurs before the tem­

perature or watt consumption decreases to 80% of the initial values. The life of the wire can be regarded as approximately proportional to the diameter of the wire. Owing to the greater solubility of the chromium of the alloys than that of the other elements in brine solution, the brine test is of little use in determining the life of wires. The peeling-off of the oxidized film is useful only in the higher ranges of temperatures. The oxygen gas test shortens the time of testing by or more of that of the air test. I t is suggested that the cracking sound test is worthy of further study.—W. A. C. N.

R esearch on E le c tric H e a tin g E le m e n ts . Isamu Asaki

(Japan Nickel Rev.,

1933, 1, 311-321).—[In English and Japanese.] The quality of a heating wire depends greatly on its chemical composition and the melting process used in producing the alloy. The deleterious effect of low-grade raw materials is emphasized. The compositions of the commercial alloys are given. The mechanical working—drawing—is receiving increasing attention at the present time, in order to attain still greater uniformity of the wires.

With good-quality wires the oxide film formed on the surfaces of heating wires is principally Cr203 which is difficult to scrape off. Forced heating is considered the most effective and practical method for the quality test.

The causes affecting the life of heating wire are discussed. Photomicrographs show the growth of the intergranular oxide films.—W. A. C. N.

F o rce d L ife Te st o f H e a tin g W ire s . Shinji Togo

(Japan Nickel Rev.,

1933, 1, 322-341).—[In English and Japanese.] A study of the physical properties of electric heating wires as applied to various heating utensils and for sundry purposes. As no single property is alone responsible for the differing lives of wires, a modified life test under stringent conditions is the only possible one for determining the comparative qualities of the elements.

The useful life,

i.e.

when the filament becomes incapable of standard heating temperature and current consumption, is not an important consideration at low heating temperature ranges, but the breakdown life,

i.e.

the life before actual failure, is extremely important. The higher the temperature the more the useful life factor enters into the question. From the results of his tests T. concludes (1) the life of a wire is affected considerably by any non-uniformity in its diameter; (2) the stronger the adhesion of the oxide films the longer the life; (3) the life depends on the rate of oxidation and also on the uniformity of the inner physical structure. See also

J. Illuminating Eng. Soc. Japan,

1928, 12, 386, and (abstracts)

Japan Nickel Rev.,

1933, 1, 380 ;

J. Inst.

Metals,

1933, 53, 347.—W. A. C. N.

T e stin g th e L ife o f a n E le c tric H e a tin g W ir e . Yasuyuki Toba

(Japan Nickel Rev.,

1933, 1, 342-346).—[In English and Japanese.] Two classes of wires are under consideration: (1) nickel 80, chromium 2 0% ; (2) nickel 60, chromium 15, and iron 25%. The lives of the wires have been deter­

mined by the time which elapses up to the point of breakdown by heating to a high temperature and then cooling them alternately at a certain time interval. The apparatus and technique employed are described and dis­

cussed.—W. A. C. N.

74 Metallurgical Abstracts

V o l . 1

D esign o f E le c tric H e a tin g D evices. Isamu Asaki (

Japan Nickel Rev.,

1933.1, 364-373).—[In English and Japanese.] A discussion which embraces the mechanical and electrical properties of the materials for the heating elements, electric heaters, heating elements under service conditions, con­

necting parts, calculations in the design of electric heaters.—W. A. C. N.

O x id a tio n Tests o f H e a tin g W ire s a t H ig h T e m p e ra tu re s . S. Togö

(Japan Nickel Rev.,

1933, 1, 379-380).—[In English and Japanese.] Summary from

J. Illuminating Eng. Soc. Japan,

1928, 12, 354—362, which was published in

Japanese. See

J. Inst. Metals,

1933, 53, 347.—W. A. C. N.

C o e fficie n t o f T h e rm a l E x p a n s io n o f H e a tin g W ire s . S. Togo (

Japan Nickel Rev.,

1933, 1, 381-382).—[In English and Japanese.] Summary from J.

Illuminating Eng. Soc. Japan,

1928, 12, 243, which was published in Japanese. See

J. Inst. Metals,

1933, 53, 347.—W. A. C. N.

E le c tric a l R esistan ce o f H e a tin g W ire s . S. Togö

(Japan Nickel Rev.,

1933.1, 383-385).—[In English and Japanese.] Summary from

J. Illuminat­

ing Eng. Soc. Japan,

1928, 12, 590-605, which was published in Japanese.

See

J. Inst. Metals,

1933, 53, 347.—W. A. C. N.

M a c h in a b le M e ta l. P. W. Rauschert

(Canning Age,

1933, 14, 447).— Describes the properties of “ Illinois ” nickel alloy and its use in handling foodstuffs in the canning and dairy industries.—E. S. H.

C atalogues [N ic h ro m e ]. Anon.

(Japan Nickel Rev.,

1933,1, 392-394).—[In English and Japanese.] Particulars of physical, chemical, and electrical properties of the most important Nichrome alloys passing under proprietary names are given.—W. A. C. N.

* L iq u a tio n o r S eg re g a tio n o f th e C o n s titu e n ts o f S ilv e r C oinage A llo ys.

S. W. Smith

(Sixty-Third Rep. Royal Mint (Lond

.), 1932, 55-57).—It has already been shown

(Sixty-First Rep. Royal Mint (Lond.),

1930, 55-60) that in the 50 : 50 silver-copper alloy the copper primaries which form at temperatures between the liquidus and the solidus are free to move in the molten matrix, and do so move under the influence of gravity if allowed sufficient time. In order to demonstrate micrographically the movements which occur in casting, copper primaries were concentrated under the influence ^ of gravity at the top of a molten cylindrical specimen of this alloy by “ soaking at a suitable temperature, and sudden chilling was then applied in their vicinity. Both micrographic and analytical evidence showed that the copper primaries had been scattered by the chilling surface and had moved away from it in strict accordance with the well-known effect of casting alloys of this composition in chill moulds under ordinary conditions. These observations were extended to other silver coinage alloys both on the copper- rich and on the silver-rich sides of the eutectic.—J. H. W.

C h e m ica l Studies o f A n c ie n t C hinese C oins.—I I . Tsurumatsu Döno

(J. Chem.

Soc. Japan,

1932, 53,100-109;

C. Abs.,

1933, 27,5).—[In Japanese.] Assay of ancient coins can be made with accuracy by means of combined chemical and microscopic tests. True ancient coins showed more lead than less ancient or imitation coins and the lead appeared in a more segregated black mass of metal under the microscope.—S. G.

S ilv e r-C o p p e r A llo y s C o n ta in in g P h o s p h o ru s .— I I I . K. W. Fröhlich

(Mitt.

Forschungsinst. Edelmetalle,

1933, 7,91-96).—See

J. Inst. Metals,

1933. 53,696.

With increasing phosphorus content the tensile strength of annealed 50: 50 copper—silver alloy decreases to a minimum with ()• 1 °() phosphorus and remains fairly steady up to 1% phosphorus after which it slowly increases reaching 'V* kg./mm.2 with 2-5% phosphorus; the elongation rises sharply to 0-1%

phosphorus then more slowly to a maximum at 1%. Phosphorus increases the rate of grain-growth on annealing, hence alloys containing this element can be annealed at lower temperatures or for shorter periods than phosphorus-

1934

Properties of Alloys 75

free alloys. T h e h ard n ess of th e allo y s is sc arcely affected b y th e p h o s p h o r s co n ten t,' b u t falls ap p rec ia b ly w ith increase in a n n ealin g

520° to 700° C .; th e E ric h se n v alu e re ac h es a m ax im u m w ith 0-1 „ phosp»hon is, th e p re c ip ita tio n -h a rd e n in g effects a re u n a lte re d , b u t t h e r a t e o fc o rro s io n in acetic a cid is decreased slig h tly . P h o sp h o ru s h as a sim ilar effect on 80 . 20 a n d 83 : 17 s ilv e r-c o p p e r allo y s.— A. R . P . .>•>- ‘im p __

♦ S tru c tu re o f SUver A m a lg a m . A. W e ry h a (Z. K n s t., 1933, 8b, 330 E x a m in a tio n b y th e X -ra y m eth o d of silv er am alg am , p ro d u c e d b y im m ersing a s d v e r w ir e in m erc u ry fo r som e tim e , show s th e presence of th e co m p o u n d A % Ho lid ific a tio n D ia g r a m o f A llo y s F o rm e d by T w o A lk a li M e ta ls i| S o d ta m - R u b id iu m A llo y s . E . R in c k (Compt. rend,., 1933, 197, 1404 ^ O b ). i n ru b id iu m fo r th e s e e x p erim e n ts w as p re p a re d p a r tly fro m th e chloride b y th e calcium re a c tio n (H ack sp ill m eth o d ) a n d p a r tly a lu m in o th e rm a lly fro m th e c arb o n a te , a n d th e n p u rified b y fra c tio n a l d istilla tio n . T h e solidificatio d iag ram does n o t resem ble t h a t of th e s o d iu m -p o ta ss m m alloys, a n d no evidence of t h e c o m p o u n d N a 2R b w as fo u n d . A e u te c tic occurs a t 7.

a to m ic -% of ru b id iu m a t - 4-5° C. T h e cu rv e te n d s to becom e h o rizo n tal in th e v ic in ity of th e com p o sitio n of a possible c o m p o u n d N a R b ,. a n d i t w as supposed t h a t fo r allo y s of th is com p o sitio n th e 2 m e ta ls w ou ld be m u tu a l y m iscible a t te m p e ra tu re s ab o v e th e te m p e ra tu re of th e beg in n in g of c ry s ta l­

lizatio n . T h e allo y s w ere show n e x p e rim e n ta lly to

tio n w hen so ak ed fo r 5 h rs. a t te m p e ra tu re s b etw een 80 a n d 2 0 0 0. inclusive.

T he re su lts in d ic a te t h a t o n ly th e s tu d y of a n o th e r p ro p e rty of th e liq u id alloys w ill e x p la in th e p a rtic u la r sh ap e of th e liq u id u s.— J . H . W .

E ffe c t o f l P re c ip ita tio n fr o m S u p e rs a tu ra te d S o lid S o lu tio n s a fte r C old- W o r k in th e H e a t E x p a n s io n D ia g r a m . F ra n z B o lle n ra th (M etallwirtschaft, 1933 12 569-573).— T he te m p e ra tu re a t w h ich p re c ip ita tio n com m ences in aged E le k tro n , L a u ta l, a n d esp ecially D u ra lu m in has been d e te rm in e d from d ila to m e tric cu rv es, as w ell as th e effect of cold-w ork on th e sh ap e of th e curves. T h e a c tu a l p re cip ita tio n is p reced ed b y a process of re a rra n g e ­ m en t of th e a to m s in th e la ttic e w h ich is c h a ra c te riz e d b y a rise m th e coeff.

of e x pansion. T h is coeff. is 22-8 X 10' 6 fo r u n w o rk e d D u ra lu m in a t 20 C., a n d falls to 21-9 X 10"6 a f te r a re d u c tio n of 2 0 /o, b y cold-rolling, te m p e ra tu re of th e beg in n in g a n d en d in g of th e p re c ip ita tio n is re d u c e d 30 G.

b v a 2 0° / re d u ctio n , a n d is o nly s lig h tly m ore a f te r a m ore severe red u c tio n . T h e^ p J e ip T ta tio n of CuA12 a n d of M g2Si c a n be recognized as se p a ra te rea In f lu e n ^ J o f R e c ry s ta U iz a tio n T e m p e ra tu re a n d G ra in -S iz e on th e Creep C h a ra c te ris tic s o f N o n -F e rro u s A llo y s . C. L . C lark a n d A. E W h ite (Rroc.

A m er Soc. Test. M at., 1932, 32 , (II), 4 9 2 -5 0 6 ; discussion, 5 0 7-516).—See / In s t M etals 1932, 50, 432. I n th e discu ssio n H ow ard Scott p o in te d o u t, fro m a" rev iew of th e wo’r k done b y o th e r in v e s tig a to rs , t h a t th e r e c ry s ta l­

liza tio n te m p e ra tu re of p u re m e ta ls is a c o n s ta n t fu n c tio n o f .th e re la x a tio n te m p e ra tu re ; th u s th e fo rm er is a b o u t 0-5 tim e s a n d t h e D t t e r a b o u t O 47 tim es th e m eltin g p o in t in ° a b s. F ro m C. a n d W . s w o rk ( T x + 2 7 3 )/(l 2 + 273) = 0-95 fo r M onel m e ta l a n d v a rio u s c o p p er-z m e alloys w h ere T * is th e te m ­ p e ra tu re a t w h ich th e creep r a te is 0-0 0 1% p e r h r. a t a lo ad of 1 0 ,0 0 0 Ib. m , a n d T 2 is th e te m p e ra tu re of m ax im u m soften in g ra te o n a n n ea lin g a llo ts cold-rolled to 8 0 -8 5 % re d u c tio n fo r 15 m in u te s. F ro m th is re la tio n i t is suggested t h a t m ore significant in fo rm a tio n on th e s tre n g th of m e ta ls a t h igh te m p e ra tu re w ill be o b ta in e d b y m ak in g creep te s ts a t th e

te m p e ra tu re or som e p re d e te rm in e d fra c tio n th e re o f. A rth u r M cCutehan has su b ie c te d th e c u rv es (on a lo g -lo g basis) giv en in th e p a p e r to m a th e m a tic a l an aly sis, a n d p o in ts o u t t h a t t h e p a ra b o la d e te rm in e d ^

p lo tte d on o rd in a ry p a p e r gives a c le are r p ic tu re of th e re la tio n of stress

76 M etallurgical Abstracts

Vo l. l to creep a n d m akes a fa irly re liab le d is tin c tio n b e tw ee n th e creep charac teristics of m ate ria l below a n d above th e re c ry s ta lliz a tio n te m p e ra tu re .— A. R . P.

in v e s t ig a tio n s o n S egregatio n. G. M asing a n d E . S ch eu er (Light Metals Research, 1933, 2, (35), 12-29).— A fu ll tra n s la tio n , in clu d in g sketches, from Z. Metallkvnde, 1933, 25, 173. See J . Inst. Metals, 1933, 53, 698.— J . C. C.

* V o lu m e - M a g n e to s tric tio n E x h ib ite d b y P o ly - a n d S in g le -C rys ta ls. 0 . v.

A uw ers (Physikal. Z ., 1933, 34, 824—827).— R e a d a t th e I X Deutschen P h y sik e rtag , S ep tem b er, 1933. [Note by Abstractor: B y volume-magneto- stric tio n of a su b stan c e is to b e u n d e rsto o d th e re la tiv e change of vol­

um e (A F /F ) acco m p a n y in g th e p ro d u c tio n of a m ag n etic field, H, in the region of a sam ple of m a te ria l of in itia l v o lu m e F .] In v e stig a tio n of the p h enom enon in th e case of single c ry s ta ls of iro n -n ic k e l a n d iro n -c o b a lt alloys show s t h a t : (1) below te c h n ic a l s a tu r a tio n p o in t th e effect is, to a first ap p ro x im atio n , n e g lig ib le ; (2) ab o v e s a tu r a tio n p o in t th e m ag n itu d e of the effect is d ire c tly p ro p o rtio n a l to th e s tre n g th , (H ) of th e e x te rn a l magnetic field, a n d th e law of p ro p o rtio n a lity is in d e p e n d e n t of th e o rien tatio n of th e c ry s ta l la ttic e w ith re sp e c t to th e d ire c tio n of th e m a g n e tic field; (3) the abscissa, H 0, on th e H ax is, c o rresp o n d in g w ith th e p o in t of intersection of th e s tra ig h t lines giving th e re la tio n of A F / F to H is sm aller in proportion as th e d irec tio n of m ag n e tiz atio n co rre sp o n d s m o re e x a c tly w ith th e direction of easiest m ag n e tiz atio n in th e c ry s ta l la t t ic e ; (4) th e in clin atio n of these s tra ig h t lines to th e H ax is depends on th e com position of th e cry stal lattice.

T he effect in th e case of P e rm in v a r m u lti-c ry s ta llin e a llo y s is sm all a n d there is considerable resem b lan ce b e tw e e n th e v o lu m e -m ag n e to stric tio n com­

p o sitio n d iag ra m a n d th e c o m p o s itio n -s tru c tu re d ia g ra m s.— J . S. G. T.

I I I . — S T R U C T U R E

(M e tallo g ra p h y ; M a cro g ra p h y ; C ry sta l S tru c tu re .) (Continued from pp. 12-14.)

M e ta llo g ra p h ic G rin d in g w ith P a ra ffin [W a x ] Im p re g n a te d w ith Abrasives.

R . L. D ow dell a n d M. J . W ah ll (Metals and Alloys, 1933, 4 , 181-182).—The use of F re n c h em ery p a p ers in p re p a rin g m eta llo g ra p h ic sections m ay be obvia,ted b y finishing th e p olishing, a f te r th e co arse e m e ry tre a tm e n t, on ro ta tin g steel discs c o ated w ith a m ix tu re of p araffin w a x a n d abrasive. Two discs a re used, th e first being c o ate d w ith w a x a n d 150-m esh Carborundum, a n d th e second w ith w a x a n d 40 0 -m esh A lu n d u m . T h e ste el discs are rotated v ertica lly , a n d th e specim en is h e ld by h a n d fla t a g a in s t th e s id e ; in th is way no a b rasiv e is w orked in to th e surface of so ft m e ta ls , th e m e ta ls do n o t become h o t, a n d no surface flow occurs, since th e w a x a c ts a s lu b ric a n t. Aluminium, m agnesium , a n d co p p er c an be p o lish ed in th e u su a l tim e w ith less residual s c ra tc h . A n a u to m a tic a p p a ra tu s fo r p o lish in g 4 sp ecim en s sim ultaneously is d escrib ed .— A. R . P .

M e th o d o f P re p a ra tio n o f L e a d a n d L e a d A llo y Cable S hea th f o r M icroscopic E x a m in a tio n . W . H . B a sse tt, J r . , a n d C. J . S n y d e r (Proc. Amer. Soc. Test.

M at., 1932, 32, (II), 5 5 8 -5 6 8 ; discussion, 56 9 -5 7 5 ).— See J . Inst. Metals, 1932, 5 0 , 485. I n th e discussion E . E . Schximachera n d G. M . Boutondetailed th e p ro ced u re fo r p re p arin g sectio n s of le a d a llo y s fo r m icrographic work used in th e B ell T elephone L ab s. T h e se ctio n s h o u ld be c u t w ith a microtome fro m a specim en w hich is so cla m p ed t h a t th e knife c u ts d iag o n ally . Rough g rin d in g is done on a N o. 1 F re n c h em e ry p a p e r a n d th e finishing on a “ 00 ” p a p e r ; finally th e sec tio n is given a few s tro k e s o n a le a th e r strip . E tching is done w ith 75° 0 ace tic acid c o n ta in in g h y d ro g e n p e ro x id e . L ead -an tim o n y a, oys a re w ash ed in stro n g so d iu m h y d ro x id e s o lu tio n , th e n rin sed in a d ilu te soap so lu tio n a n d d rie d in a c u rre n t of a ir ; in th is w a y a tran s p are n t