T he Journal of Industrial and Engineering Ghemistry
Pub l i s hed b y T H E A M E R I C A N C H E M I C A L S O C I E T Y
AT B A S T O N , P A .
Volume VII F E B R U A R Y , 1915 No. 2
BOARD OF EDITORS Editor:
M .C .
Wh i t a k e rA ssistant Editor:
Le o l aE .
Ma r r sAssociate Editors: G . P. A d am son , E . G . B a ile y , H . E . B arn a rd , G. E . B a rto n , A . V . B le in in ge r, W m . B lu m , f f m . B r a d y , C . A . B row n e, F . K . C am ero n , W m . C am p b e ll, F . B . C a rp e n te r, C . E . C a s p a ri, V . C o b le n tz , W . C . G eer, W . F . H illeb ran d , W . D . H orne, T . K a m o i, A . D . L ittle , C . E . L u ck e , P . C . M c llh in e y , J. M . M a tth e w s , T . J. P ark e r, J. D . P en n o ck , C liffo rd R ich a rd so n , W . D . R ich a rd so n , G . C . S to n e, E . T w itc h e ll, R . W a h l, W . H . W a lk e r, W . R . W h itn e y , A . M . W rig h t.
P u b lish ed m o n th ly . S u b scrip tio n price to n o n -m em b ers of th e A m erican C hem ical S o ciety , $6.00 y early . F oreign p o stag e, sev en ty -fiv e c en ts, C an a d a , C u b a a n d M exico excepted.
E n te r e d as Second-class M a tt e r D ecem b er 19, 1908,'a t th e Post-O ffice a t E a s to n , P a ., u n d e r th e A c t of M a rc h 3, 1879.
Contributions sh ou ld be addressed to M. C. W hitaker, Columbia U n iv e r sity , N ew York City
C om m unications co n cern in g ad vertisem en ts should be se n t to T h e A m erican C h em ical S o c ie ty , 42 W est 39th St., N ew York City S u b scrip tion s and cla im s lor lo st co p ies sh ou ld be referred to Charles L. P arson s, B ox 505, W ashington, D. C.
Es c h b n b a c h Pr i n t i n g Co m p a n y, Ea s t o n. Pa.
Ed i t o r i a l s:
A n n u al E lectio n and R ep orts of O ur S o c ie ty . Or i g i n a l Pa p e r s:
T ita n iu m and I ts E ffects on Steel. B y G eorge F .
C o m s to c k ... 87
M an gan ese S teel. B y John H . H a ll... 94
T h e C om position of P a in t V apors. B y C . A . K le in . . . . 99
A S tu d y of V arious T ests upon G lue, P a rticu larly th e T en sile S tren gth . B y A u g u stu s H . G i l l . 102 A C om parison o f V arious M od ifications of th e K je ld a h l M eth o d w ith the D um as M ethod of D eterm in in g N i trogen in C o a l, w ith N o tes on E rrors in the D um as M eth o d D u e to N itrogen E v o lv e d from th e C op p er O xide. B y A m o C . Fieldner and C arl A . T a y lo r. . . 106
T h e D eterm in ation of G asoline V a p o r in A ir. B y G . A . B u rrell and I. W . R o b e rtso n ... 112
T h e C olo rin g Principle of M y rica R u b ra — I ts A zo-, Sulfide and N itro -D yestu ffs. B y S adak ich i S ato w . 113 O n a S tarch -F o rm in g E n zym e from M a lt : Its A ction on H em icelluloses and Its Com m ercial A p p licatio n to B rew in g. B y C harles B . D a v is ... 115
La b o r a t o r y a n d Pl a n t: T h e U se o f H ydrom etallu rgical A p p aratu s in C hem ical En gin eerin g. B y John V . N . D o r r... 119
A Sim p le F a t E x tractio n T ub e. B y C . A . B u t t 130 Ad d r e s s e s: T h e W a r and the C hem ical Ind ustry. B y W m . H . N ic h o ls... 131
P a in tin g D efects: T h e ir C auses and Prevention . B y G u s ta v e W . T hom pson^... •... 136
F eld sp a r as a Possible Source of A m erican P otash . B y A . S. C ushm an and G . W . C og g esh all... 145
A sp e cts of Som e C hem ical Industries, in th e U n ited S tates, T o d a y . B y E d w ard G u d e m a n ... 151
T A B L E O F C O N T E N T S 1 O b i t u a r i e s : 86 : C harles M a rtin H a ll... Sam uel B en ed ict C h r isty . Cu rren t In d u strial Ne w s: M etals in 1914...•>>!*.■.*! S7 T h e Rennerfelt Electric Furnace... 159
Quality of Sulfate of Ammonia for E x p o rt... 160
Danish Engineers and the United S ta tes... 160
Consumption of Gas in I t a ly ... 160
Patents in W ar T im e ... 160
Notes and Co r r esp o n d en ce: Concerning the N utritive Value of Vegetable Ivory— Preliminary N otes... 161
Annual M eeting of the American Chem ical Society— 19 15... 161
Nitrogen-Protein T a b le ... 161
Benzol Products in the United S ta tes... 161
Searles Lake Potash— A Correction... 162
Sodium Alizarinsulfonate as an Indicator in Ammonia Titrations in Nitrogen Determ inations... 162
Personal No t e s... 163
Governm ent Pu b l ic a t io n s... 165
Book Re v ie w s: Geschichte des Elektroeisens m it besonderer Berück sichtigung der zu seiner Erzeugung bestimmten elek trischen O fen ... 170
The M icroscopy of Drinking W ater... 170
Van Nostrand's Chemical A nnual... 170
Practical Handbook for Beet-Sugar C hem ists... 170
New Pu b l ic a t io n s... 171
Recen t In v e n t io n s... 172
Ma r k e t Re p o r t... 174
86 T H E J O U R N A L O F I N D U S T R I A L A N D E N G I N E E R I N G C H E M I S T R Y Vol . 7, No. 2
EDITORIALS
A N N U A L E L E C T IO N A N D R E P O R T S O F O U R S O C IE T Y
T h e results of th e b allo t-fo r th e electio n of officers o f th e A m erican C h em ical S o cie ty are record ed in th e J a n u a ry n u m ber of th e Journal of th e S o c ie ty . P rofessor C h arles H. H e rty w as elected P resid en t of th e S o cie ty for th e ye a r 1915. T h e new directors, electe d for three y e a rs beginning J a n u a ry 1, 19 15 , are A lexan d e r S m ith and E . G . L o ve . T h e cou n sellors-at-large for th e th ree -ye ar te rm are E . C . F ra n k lin , P. K . C am eron , G . B . F ra n k fo rte r, and G . A . H u le tt.
C h a r l e s H o lm e s H e rty w as born at M illed geville, G eorgia, D ecem ber 4, 1867.
H e atten d ed th e U n i
ve rs ity of G eorgia for h i s u n d e r g r a d u a t e train in g , receivin g th e degree of P h .B . in 1886. E n te rin g Johns H o p k i n s U n iv e rsity , he pursued g ra d u ate courses in C h e m istry , M in eralo g y and G eo l
o g y, and received th e P h .D . degree in 1890.
In 1891 he becam e in stru cto r in ch em istry in th e U n iv e rsity of G eo rgia and he serve d as a d ju n ct professor th e re fro m 1894 until 1902. W hile on lea ve of absence, 1899-1900, h e s t u d i e d u n d e r W e r n e r a t Z ü r i c h and w ith W itt and vo n K n o rre a t Berlin.
In consequence of a c o n v e r s a t i o n w i t h W itt,h is atten tio n was d irected to th e w a ste
f u l m e t h o d s p r a c ticed in th e tu rp e n tine in d u stry in A m e r
ica. R e t u r n i n g t o G eo rgia he b egan in ve stig atio n s in th e southern field, using th e ap p a ratu s now
k now n as th e ‘ H e rty C u p .” T h is pioneer w o rk requ ired great p a tien ce and ste a d fa st confidence in th e correctn ess of his vie w s and in v o lv e d m uch lab o r and t a c t in m eetin g th e op positio n of p reju d ice an d ignorance. In 1902 he resigned his position in th e U n iv e rsity of G eo rgia to accep t one w ith th e U n ite d S ta tes B u re au of F o re stry . In th e Sum m er o f 1903 he stu d ied th e tu rp e n tin e in d u s
t r y in sou th w estern F ra n ce and in A u s tria an d th e m a rk etin g of n a v a l stores in L ondon . In 1904 he
Ch a r l e s Ho l m e s Hu r t y. Pr e s i d e n t Am e r i c a n Ch e m i c a l So c i e t y
resigned his p o sitio n w ith th e B u re au of F o r e s tr y and d e v o te d his en tire tim e to secu rin g th e m a n u fa c tu re of his cu p s on a large co m m ercia l scale and su p e rv isin g th e ir in s ta lla tio n in a large n u m b er of d is
tricts. M o re th a n a h u n d red m illion o f th ese cu p s are now in use. T h e s a v in g in resinous p ro d u cts and in th e u tiliza tio n o f trees as lu m b e r has b een v e r y g re a t.
In 1905, D r. H e rty b ecam e p rofessor of gen eral and in d u stria l c h e m istry in th e U n iv e r s ity o f N o rth C a r o lin a and since t h a t tim e he h as p u b lish ed a n u m b er of i n v e s t i g a t i o n s u po n v o la tile oils, resins, e tc., e sp e c ia lly in re la tio n to th e va rn ish , p a in t, and soap in d u stries. H e h as also
■ fo u n d o p p o rtu n ity for som e im p o rta n t re search es in in o rg an ic c h e m istry , p a r t i c u la r ly in th e field of d ou ble sa lts an d co m plex am m o n ia c o m p o u n d s and in co n n ectio n w ith th e h y p o th esis of W ern er, w here he has rendered v a lu a b le se rvice . H is rap id m eth o d fo r d e
te rm in in g oil in c o tto n seed p ro d u cts is w id e ly used an d h as p ro v e d , m ost u sefu l in th is im p o rta n t so u th ern in d u stry .
T h e rep o rts of th e v a rio u s officers also p u b lish ed in th e J a n u a ry n u m b er of th e Jo u rn a l of th e S o c ie ty p rese n t a g re a t d eal of m a te ria l w h ich e v e r y m em b er w ill find in te re s tin g an d in s tr u c t
iv e . T h e A m e rican C h e m ic a l S o c ie ty is now th e la rg e st te c h n ical s o c ie ty in th e w o rld , en ro llin g o v er 7,17 0 a c tiv e m em bers.
Its lo c a l a c tiv itie s are d ivid e d in to fo r ty -fiv e lo ca lse ctio n s.
T h e s o c ie ty d istrib u te s 360,000 copies of its jo u rn a ls per y e a r— alm o st 1,000 copies per d a y . T h e B o a rd of D ire c to rs a d m in isters a b u d g e t of o v e r $104,000 per y e a r.
A carefu l s tu d y of m a n y of th e item s se t fo rth in
th ese rep o rts m u st c e r ta in ly im p ress th e rea d e r w ith
th e su b sta n tia l gro w th an d fa r-re a ch in g in flu en ce of
th e A m e rican C h em ical S o c ie ty and its v a lu a b le service
to th e ch em ical and oth er scie n tific professions.
Feb. , 1 91 5 T H E J O U R N A L O F I N D U S T R I A L A N D E N G I N E E R I N G C H E M I S T R Y S 7
ORIGINAL PAPERS
T IT A N I U M A N D I T S E F F E C T S O N S T E E L 1 B y G e o r g s F . C o m s t o c k
T ita n iu m is one of th e chem ical elem ents w hich is w id e ly d istrib u te d in th e e a r th ’s crust in sm all q u an titie s b u t is n o t esp ecially a b u n d an t. I t has a v e r y stro n g a ffin ity for o x yge n , and is a lw a y s fou n d in n a tu re as an oxide, its principal ores b eing ru tile , th e fa irly p u re dioxide, and ilm enite, a m ixtu re of iron an d tita n iu m oxides. One of th e e lem e n t’s chief p e cu lia ritie s is th e readiness w ith w hich it com bines w ith n itro g en . I t is one of th e v e ry fe w elem ents w h ich w ill “ b u rn ” in an atm osphere of n itrogen . Its dioxid e is one of th e m ost stab le com pounds know n , and th e exp en d itu re of g rea t en ergy is requ ired to d ecom po se it. T h u s it follow s th a t w hen tita n iu m is se p a ra te d fro m its o xyge n , it w ill re a d ily re-com bine w ith it an d en ergy w ill be e v o lve d again in th e .fo r m of h ea t.
T h e v a lu e of tita n iu m in th e steel in d u stry is due la rg e ly to th e fa c t th a t its dioxide is so m uch m ore s ta b le th a n iron oxide th a t its actio n in ro b b in g m elted steel o f its o x y g e n , or “ d eo xid izin g” it, is v e r y p o w erfu l.
In order to o b tain tita n iu m in a form useful for th is purpose, it is n ecessary to reduce th e oxides fo u n d in n atu re to som e m etallic sta te . T h ere are tw o k n o w n w a ys of d oin g th is: (1) b y reduction w ith carbo n under th e in ten se h e a t of th e electric arc, form in g a carbid e of tita n iu m ; (2) b y an alu m in o-th erm ic reactio n , w h e re b y alu m in u m is oxidized a t a high te m p eratu re a t th e exp ense of th e tita n iu m , and an a llo y of tita n iu m , alu m in u m and iron is produced. T h e carbid e of tita n iu m is th e form m ost ge n e rally used, for reasons th a t w ill be exp lained below .
B efo re proceedin g to consider th e effects of tita n iu m on steel, it m a y be well to explain m ore cle a rly th e relatio n of th e elem ent to th e com pounds m entioned a b o v e . A rra n g e d in th e order of in creasin g s ta b ility w e h a v e th e series:
T ita n iu m ,
T ita n iu m carbide, T ita n iu m n itride, T ita n iu m oxide.
E a c h m em ber of th is series tend s under fa v o ra b le con d itio n s to be c o n v erted in to one of th e fo llo w in g m em bers. T h u s m etallic tita n iu m when h eated to redness in p u re n itro gen form s tita n iu m n itrid e, b u t w hen h e a te d in air on ly, th e oxide is form ed. T h e nitride w hen h e a te d to redness in air is slo w ly c o n v erted to th e oxid e, b u t th e carbid e burns vig o ro u sly in air, fo rm in g tita n iu m dioxide. T h e reverse reactio n , d riv in g th e oxide b ack to carbide, ta k e s place o n ly at v e r y h igh te m p eratu re s and w ith th e ex p en d itu re of g r e a t en e rg y . E v e n a t th e te m p eratu re of th e b la st fu rn a ce tita n ife ro u s ores do n ot giv e m ore th a n 1 per c e n t o f tita n iu m in th e pig iron. T h is is p ro b a b ly p resen t p a r tly as carbid e and p a rtly as cya n o n itrid e, a m ix tu re o f carbid e and n itride. A lth o u gh in th e
■ P rese n ted before th e N ew Y ork Section of th e Society of C hem ical In d u s try , C h e m ists’ C lu b , N o v em b er 20, 1914.
b la st fu rn a ce tita n iu m n itrid e is so m e tim es form ed , it is n o t p rese n t in th e tita n iu m -c a rb id e a llo y used in tr e a tin g steel, fo r a t th e te m p e ra tu re of th e e le ctric a rc fu rn a ce an d w ith th e red u cin g atm o sp h ere and excess carb o n used, th e n itrid e is d isso ciated in fa v o r of th e carbid e.
B esides tita n iu m , th e re are o th e r elem e n ts th a t are used m ore or less fr e q u e n tly to d eo xid ize steel.
A m o n g th ese are alu m in u m , m an gan ese an d silicon.
T h e c o m p a ra tiv e e fficien cy o f th ese elem e n ts as “ co r
r e c tiv e a g e n ts ” fo r d e fe cts in ste el in g o ts w as th u s ta b u la te d b y P ro f. B ra d le y S to u g h to n in an a rticle a p p e arin g in th e Railw ay Age Gazette, F e b . 7, 1913 , th e elem ents b ein g g iv en in th e ord er o f th e ir e ffe c t iv e ness:
1 2 3 4 5
P rev e n tio n of blow holes... . ... A1 T i Si V M n R em o v al of oxides of F e an d M n ... T i Si (w eakly)
H indering this removal... .4/ M n R em o v al of all oxides a n d slag enclosures T i
H indering this rem oval... A l R em o v al of n itr o g e n ... T : V(?) B reaking u p a n d rem o v al of iron su lfid e M n T i(?)
C au sin g a p ip e ... ... Al Si T i V M n H in d erin g seg reg a tio n ... Al T i V
Prom otion o f segregation... M n S i (som etim es)
A general o u tlin e of th e in flu en ce of tita n iu m on steel is g iv e n a b o v e and a t th e sam e tim e it is sho w n th a t for ge n e ra l e ffe ctiven ess tita n iu m is th e b est of th e v a rio u s deoxidizers used. F o r th e se p u rp o ses th e carb id e is a t lea st as v a lu a b le as th e p u re m etal in regard to th e resu lts o b ta in ed . A s to expense th e re is a v e ry g rea t d ifference in fa v o r of th e carb id e , as th is can be o b ta in e d in carlo ad lo ts fo r 8 cen ts per lb . w ith a tita n iu m co n te n t of 15 to 20 per cen t, w hile th e co st of m e tallic tita n iu m w ou ld be p ro h ib itiv e . T h e m aterial sold a t th is p rice is k n o w n as “ F erro C a r b o n -T ita n iu m ,” and is m ade a t N ia g a ra F alls, N . Y . I t consists o f m icroscop ic p a rticle s o f tita n iu m carbid e held in a ‘ m a trix sim ilar to g r a y ca st iron.
W h en a d d e d to m elted steel th e m a trix d issolves q u ic k ly , and th e p a rticle s of tita n iu m c arb id e are r a p id ly diffused th ro u g h o u t th e b a th , w h ere th e y re a ct w ith g re a t v ig o r on th e o x y g e n p resent.
T h e alu m in o th e rm ic a llo y , w h ich co n ta in s v e r y little carbo n, is of course an a llo y of b o th alu m in u m and tita n iu m in iro n, an d hen ce its use p ro d u ces th e a b o ve-m en tio n ed e ffe cts o f b o th th e se elem en ts.
T h e chief o b je c tio n to th e use o f alu m in u m is its h arm fu l effe ct in h in d e rin g th e re m o v a l of o xid e and slag enclosures. A lu m in u m oxide, w h ich is fo rm ed w hen steel is d eoxid ized b y th is elem en t, is e x ce e d in g ly infu sib le, an d its te n d e n c y to w a rd m a k in g all m e ta l
lu rg ica l slags in fu sib le and visco u s is n o to rio u s. H ence th ese p a rticles o f a lu m in a (m ore or less p ure) so lid ify in steel as soon as th e y are fo rm ed , an d h a v e no te n d en cy to rise in to th e slag a t th e to p o f th e ,la d le or m old. M o re o ve r, b y m ixin g w ith o th e r sm a ll slag inclu sion s in th e steel, th e a lu m in a m akes th e m m ore' visco u s, an d h elp s to k eep th e m b a c k in th e m etal.
In the sam e w a y w h en silicon alo ne is used to d eo xid ize
steel, th e m etal is filled w ith sm all in clu sion s of iron
and m angan ese silica te s, w hich do n o t re m o v e th e m
selv es b efore solid ificatio n .
88 T H E J O U R N A L O F I N D U S T R I A L A N D E N G I N E E R I N G C H E M I S T R Y Vol . 7, No . 2 T ita n iu m oxide, h ow ever, a cts as a flux for silica te s alu m in u m , i. e., in th e fo rm o f th e carb id e . T h e an d o th er slags th a t m a y be in th e steel, m a k in g th e m a lu m in o th e rm ie a llo y sh o u ld be used o n ly in th e fluid enough to rise to th e top of th e m etal and pass fe w rare cases w here th e carb o n of th e ferro in to th e slag under conditio ns th a t m igh t o th erw ise ca rb o n -tita n iu m a llo y co u ld n o t be to le ra te d in th e h ave held th em b ack in th e m etal. V ario u s researches steel. In so ft steels th e increase in carb o n co n te n t
F io . 1—S u l f u r P r i n t s o p U n t r e a t e d " A ” R a i l s T h e b lack sp o ts in d icate w here sm all sulfide inclusions are th ic k ly segregated.
h a ve d em on strated this a ctio n of tita n ic oxide in ren dering slags m ore fluid, w hen added in n o t to o large am ounts. T h u s it is seen th a t th e b est clean sing actio n is o b tain ed when th e tita n iu m is ad d ed w ith o u t
F i g . 2 S u l f u r P r i n t s o f T i t a n i u m - T r e a t e d " A ” R a i l s T h e sm all size an d u n ifo rm d is trib u tio n of th ese sp o ts are ch arac te ristic of tita n iu m -tre a te d rails.
fro m th is ad d itio n as u su a lly p ra ctic e d w o u ld n o t be
m ore th a n a b o u t 0.01 per cen t so th a t th e cases w here
th is w ou ld m ake a n y m a terial d ifferen ce are v e r y few
indeed. P r a c tic a lly all th e tita n iu m used in ste el in
Feb. , 1 91 5 a T H E J O U R N A L O F I N D U S T R I A L A N D E N G I N E E R I N G C H E M I S T R Y 89 th is c o u n try a t th e present tim e is in th e form of ferro
ca rb o n -tita n iu m , and a large p e rcen tage of th is is used fo r rail steel, a lth o u gh its use in o th er steels is gro w in g s te a d ily .
“ T ita n iu m s te e l,” p ro p erly sp eakin g, is n ot m ade co m m e rcia lly a t present. Such a title n a tu ra lly im plies a ste el w hose prop erties are dep en den t to an a p p re ciab le e x te n t on a 'c e r ta in co n ten t o f tita n iu m . B u t th e a d v a n ta g e s of th e tita n iu m -tre a te d steels as m ade to d a y are due to greater soundness, cleanness, and less seg regatio n , and not, as fa r as we k n o w a t p rese n t, to th e sm all am o u n t of tita n iu m le ft in th e solid m etal. In no case has o ver 0.025 Per cen t of tita n iu m been fou n d in an y sam ple of tita n iu m -tre a te d
ta n iu m , b u t m o st of th is elem e n t is used in Open- H e arth steel on a cc o u n t o f th e g re a te r to n n ag e of th is m a terial m a n u fa ctu re d . T h e a llo y is fu rn ish e d in v a rio u s sizes, fro m lu m p s of a b o u t x in ch d iam eter to p o w d er, a cco rd in g to th e q u a n tity of steel to be tre a te d a t one tim e. F o r th e b e st resu lts it m u st be ad d ed to th e m elted steel as it flow s fro m th e fu rn a ce to th e lad le. T h e a d d itio n m u st of course be e n tire ly co m p leted before th e sla g has b egu n to flow o u t on to p of th e m etal. A fte r th e a d d itio n , th e ste el m u st be held in th e lad le for from 3 to 10 m in u tes, d ep en din g on th e size of a llo y used and th e m ass of steel tre a te d , to allow th e tita n iu m to b ecom e th o ro u g h ly diffu sed , th e d eo xid izin g rea ctio n s to ta k e p lace, an d th e tita n iu m
T o p s o f H e a d s U p p e r C e n t r a l P a r t s o f W e b s B o t t o m s o f F l a n g e s F i g . 3— T y p i c a l U n t r e a t e d ( U p p e r ) a n d T i t a n i u m - T r e a t e d ( L o w e r ) “ A ’ R a i l s X 100: R e d u c e d b y O n e - F o u r t h
T h e a b o v e s a m p l e s ( e t c h e d w i t h p i c r i c a c i d ) s h o w d a r k c r y s t a l s o f p e a r l i t e w i t h l i g h t s t r e a k s o f f e r r i t e b e t w e e n , e x c e p t i n t h e w e b o f t h e u n t r e a t e d r a i l . T h i s r a i l w a s b a d l y s e g r e g a t e d , a n d h a d a v e r y h a r d a n d b r i t t l e s p o t i n i t s w e b . P a r t o f t h i s s p o t i s s h o w n a b o v e , m o s t l y p e a r l i t e w i t h o n e l o n g , l i g h t c r y s t a l o f c c m e n t i t e o r i r o n c a r b i d e . N o t e t h e s e a m s a t t h e t o p o f t h e h e a d o f t h e u n t r e a t e d r a i l , a n d t h e s c a r c i t y o f p e a r l i t e a t i t s u p p e r a n d l o w e r e d g e s .
ste el a n a ly z e d a t our lab oratories. Of course it is p o ssible t h a t th is v e r y sm all tita n iu m co n ten t is in som e w a y asso ciated w ith im purities so as to d istrib u te th e m u n ifo rm ly , th u s p reven tin g segregation , b u t we do n o t k n o w t h a t th ere is a n y such associatio n and h en ce are n o t ju stified in considering tita n iu m -tre a te d ste el as a tru e a llo y steel. U nder th e usual cond itio ns o f m a n u fa ctu re it is v e r y difficult to m ake steel absorb m ore tita n iu m th a n th e 0.025 per cen t n o ted a b o v e and no use th a t w ould w arran t 'the com m ercial p ro d u ctio n o f a real “ tita n iu m ste el” has y e t been fou n d for a p ro d u c t co n tain in g larger q u an tities.
S teels m ade b y th e B essem er, O p en -H earth , or C ru c ib le processes m a y be, and are, tre a te d w ith ti-
and oth er oxides to rise o u t of th e m etal in to th e slag.
T h en th e steel is te em ed as usual in to th e m old s w here no fu rth e r a d d itio n s sh o u ld be m ade.
T h e a m o u n t of a llo y recom m en ded fo r use in rail steel is 13 lbs. p er to n , w h ich m eans, Since th e ferro carb o n -tita n iu m is g u a ra n te e d to c a r r y o v e r 15 per cen t tita n iu m , an ad d itio n o f 0.1 p er ce n t of m etallic tita n iu m . A h ig h er grad e a llo y is n o t used b ecau se its ra te of so lu tio n in th e m elted ste el w o u ld b e slow er.
T h e p rice of rails tr e a te d in th is w a y is a b o u t 5 per cen t
a b o v e th e p rice o f o rd in a ry rails. F o r ca stin g s and
so ft steels a sm aller a m o u n t o f a llo y m a y b e a d d e d ,
b u t in e v e r y case it is im p o rta n t to allo w tim e fo r th e
reactio n to ta k e p la ce co m p le te ly in th e lad le, b efo re
F io . 4—T i t a n i u m C a r b i d e X 100 R ed u ced b y O n e-fo u rth
M ad e in lab o ra to ry . L arg e ro u n d e d g rains a re lig h t vio let color. N e tw o rk is yellowish w hite, p ro b a b ly iron carbide.
B lack sp o ts are p its caused b y g rinding. N o t etched.
F io . 5—T i t a n i u m C a r b i d e X 2 0 0 R ed u ced b y O n e-fo u rth
N e a r to p , dissolving in to steel below w ith p artic le s of c arb id e sc a tte re d th ro u g h th e steel. N o t etch ed .
F i g . 6 — F e r r o C a r b o n - T i t a n i u m X 1 0 0 R ed u c e d b y O n e -fo u rth
B lack s tre a k s a re g ra p h ite . R o u n d ed g rain s sta n d in g o u t in relief a re tita n iu m c arb id e. N o t etch ed .
F i g . 7— Fe-T i-A l A l l o y X 1 0 0 R ed u ced b y O n e -fo u rth
T itan iu m ab o u t 12 p e r cen t, a lu m in u m a b o u t 6 p e r c e n t a n d carb o n a b o u t 0 . 5 p er c en t. E tch ed w ith HNOa.
T h e tw o g rea t a d v a n ta g e s of w ell-d eoxid ized steel are ( i) soundness, or freed o m from blo w h oles, and (2) absence of excessive seg regatio n . T h e m a k in g o f b o th B essem er and O p e n -H earth steel is e sse n tially an oxid atio n process, th e carb o n being b u rn ed o u t of pig-iron in each case, and th e steel n ecessarily co n tain s a considerable q u a n tity of oxide w hen first m ade.
If this is n o t rem oved before so lid ification begins, th e iron oxide in th e steel con tin u es re a ctin g w ith th e carbon, fo rm in g carbon m onoxide, a gas w hich p asses up co n tin u a lly in sm all b u b b les to th e su rface o f th e m etal, where it burns w ith a bluish flam e. If som e of
F i g . S— F e-T i-A l A l l o y X 4 0 0 R ed u ced b y O n e-fo u rth
Alloy of Sw edish iro n w ith n lu m iu o th erm ic fe rro tita n iu m , show ing inclusions of a lu m in a.
N o t etch ed .
F i g . 9— Fe-T i-A l A l l o y X 200 R ed u c e d b y O n e -fo u rth
P in k c ry s ta l of tita n iu m n itrid e in a lu m i
no th erm ie fe rro tita n iu m . T h e b lack sp o ts a re p its cau sed b y g rin d in g . N o t etch ed .
“ p ip e ,” w ill fo rm in th e cen ter of th e u p p er p a r t of th e in g o t. T ita n iu m m a y cau se p ip in g , as w ell as o th er deoxidizers, b u t b y p ro p e rly d esig n in g th e m olds p ip in g m a y be co n tro lled so as n o t to g iv e m uch tro u b le .
T h e dependence of seg rega tio n on d e o x id a tio n is less o b vio u s th a n th a t of soundness. P rim a rily , of course, segregatio n is due to se le ctiv e freezin g. T h e freezin g- p o in t d iag ra m of th e iro n -c a r b o n a llo y s sh o w s th a t w ith o rd in a ry steel th e first m etal to freeze is of lo w er carb o n co n te n t th a n th e rem ain in g liq u id , an d th e la s t liq u id to freeze is of h igh er carb o n co n te n t th a n th e a lre a d y fro zen solid. B u t w ith w ell-d eo xid ized ste el th is th e steel ge ts in to th e m olds. T h e h e a t of th e reactio n
w ill u su a lly p rev en t th e fo rm atio n o f a sku ll in th e lad le, and it is n o t n ecessary to ta p th e steel h o tte r fro m th e fu rn ace to allow for cooling w hile th e ladle is b ein g held.
Sm aller am ou nts of tita n iu m h ave been tried in rail steel, w ith th e usual p recau tion s of h old in g in th e lad le, etc., b u t th e b est results h a ve n o t been ob tain ed . T h is in d icates not on ly th a t it is n o t safe to skim p th e am o u n t added, b u t also th a t m erely h old ing th e steel in th e lad le will n o t giv e th e cleanness and h o m o gen eity th a t resu lt from th e tita n iu m tre a tm e n t.
9o ' T H E J O U R N A L O F I N D U S T R I A L
th ese gas b u b b les are tra p p e d in th e fre e zin g m etàl
before th e y can escap e, b lo w h o les are form ed , and
th ese holes m a y be w eld ed to g e th e r w hen th e steel is
rolled or fo rge d . L o w -ca rb o n steels, ev en if tre a te d
w ith tita n iu m , a lw a y s co n tain b lo w h o les, b u t, th e
steel b ein g n o rm a lly clean sed b y th e tita n ic oxid e,
th e y are free fro m sla g an d are closed up w hen th e
in g o ts are w o rked . If th e y b ecom e oxid ized , h o w
ever, or c o n tain slag, th e y w ill open up as seam s or
rem ain as sla g in clu sion s in th e m etal. I t is w ell
k n o w n th a t if steel is c o m p le te ly d eo xid ized , and no
blo w h oles are fo rm ed , a large sh rin k a ge c a v it y , or
A N D E N G I N E E R I N G C H E M I S T R Y Vol . 7, No. 2
Feb. , 1915 T H E J O U R N A L O F I N D U S T R I A L A N D E N G I N E E R I N G C H E M I S T R Y 91 se le ctiv e fre e zin g ta k e s place in a q u iet m ass of p a s ty
m a te ria l, and th e high er carbon liqu id is so in tric a te ly e n ta n g le d in th e lo w er carbon solid th a t it does not h a v e a ch an ce to co lle ct in the cen ter of th e in g o t to a n y g re a t e x te n t, and is fin ally frozen to g eth er w ith th e lo w er carb o n m aterial. T h e actio n is so m ew h at lik e th a t of a sp onge h old ing w ater. B u t assum e th a t th is ste el is n o t w ell deoxidized, b u t is giv in g off gas, p ro d u ced b y th e reactio n FeO + C = F e + C O , d u rin g so lid ificatio n . T h is gas, being of course m uch
w ill be excessive seg regatio n . P h o sp h o ru s is su b je ct to th is a ctio n in th e sam e w a y as carb o n ; su lfu r, ex
istin g in th e steel as sm all n o n -m etallic globules, co m p o sed of a m ixtu re of iro n and m an gan ese sulfides w ith a freezin g p o in t n o t m u ch , if a n y , h ig h er th a n th a t of th e m e tal, is'e v e n m ore a ffected . [For th is e x p la n a tio n of th e relatio n b etw e en se g reg a tio n an d oxides in steel, th e w riter is in d e b te d ter M r. N . P e tin o t, M e ta llu rg ist o f th e T ita n iu m A llo y M a n u fa c tu r in g C o .]
A lu m in u m , and p ro b a b ly also v a n a d iu m an d silicon,
Fi g. 1 0 — Ti t a n i u m Ni t r i d e X 1 0 0 R e d u c e d b y O n e - f o u r t h
M a d e i n l a b o r a t o r y . T h e r o u n d e d g r a y g r a i n s a r e b r i g h t y e l l o w a n d a r e p r o b a b l y f a i r l y p u r e n i t r i d e . T h e w h i t e s u b s t a n c e i s p r o b a b l y c a r b i d e , a n d t h e b l a c k , o x i d e . N o t e t c h e d .
F i g . 1 1 — S t e e l C o n t a i n i n g T i t a n i u m N i t r i d e X 4 0 0
R ed u ced b y O ne-fo u rth P in k c ry sta l in lon g itu d in al section from w eb of tita n iu m - tre a te d steel ra il. N o t etch ed .
F i g . 12— S t e e l C o n t a i n i n g T i t a n i u m N i t r i d e X 200 R ed u ced b y O n e-fo u rth
T h e th re e la rg e r sp o ts a re p in k c ry s ta ls in cross section of w eb of tita n iu m -tre a te d stee l ra il. N o t etch ed .
F i g . 13— A l u m i n a S e g r e g a t i o n i n U n t r e a t e d R a i l X 200 R ed u ced b y O ne-eighth
In c lu sio n s in th e cross section of th e w eb " of a n u n tre a te d rail.
T h e se a re d a rk b lu ish g ray in color. B y chem ical an aly sis 0.003 p e r c e n t of a lu m in a was found here. N o t etched.
lig h te r th a n th e m etal, has a stron g te n d e n cy to rise;
in risin g w h ile th e m etal is in a p a s ty con d itio n , p a rt liq u id and p a rt solid, it opens up passages th ro u gh th e ste el, an d each bu bble of gas w ill ta k e u'ith it a little o f th e h igh er carbon liquid to w ard th e to p and cen ter of th e in g o t le a vin g th e solid low er carbo n m a te rial b eh ind . T h is action, m u ltiplied m an y tim es b y th e m illio ns o f gas b u bbles given off, w ill resu lt in th e fo rm a tio n of a larg e b o d y of higher carbon m aterial in th e u p p er p a rt of th e in got, or in oth er w ords, th ere
Fi g. 14— Si l i c a t e Se g r e g a t i o n i n Un t r e a t e d Ra i l X 2 0 0 R e d u c e d b y O n e - e i g h t h
S i l i c a t e , o r s l a g , i n c l u s i o n s i n a c r o s s s e c t i o n o f t h e w e b . N o t e t c h e d .
h a v e an effe ct on seg rega tio n sim ilar to th a t o f tita n iu m ,
b u t w ith v a n a d iu m th e co st of th is e ffe ct w ou ld be
h igh er, and w ith th e ch eap er a g e n ts, silicon an d
alu m in u m , n o t o n ly w o u ld th e cle an sin g a ctio n o f th e
tita n iu m d ioxid e b e la ck in g , b u t im p u ritie s (silicates
or alu m in a) w o u ld be ad d ed to th e ste el. In th is co n
nection it sh o u ld b e n o ted th a t in m o st rail ste el th a t
has been p ro p e rly tre a te d w ith tita n iu m , v e r y sm a ll,
h a rd , a n g u la r, p in k in clu sion s can be fo u n d w ith th e
m icroscop e. T h ese are tita n iu m n itrid e, p o ssib ly
92
T H E J O U R N A L O F I N D U S T R I A L A N D E N G I N E E R I N G C H E M I S T R Y Vol. 7, No. 2 c o n tam in ated w ith carbid e, and show th a t th e tita n iu m
h as com bin ed w ith som e of th e n itrogen d issolved in th e steel, and sep arated it in this form . A n a vera ge of m an y n itrogen determ in atio n s m ade in our la b oratories b y an im p ro ved m ethod on tita n iu m -tre a te d rails show s a d istin ctly low er a m o u n t present in solution in th e m etal, th an in u n tre a te d rails. N o m ethod is k now n for d eterm in ing n itrogen th a t is com bined w ith tita n iu m in th is form . T h u s th e dif-
th is fo rm th a n a n y o th er n o n -m etallic in clu sio n s of th e sam e size. A s th e tita n iu m n itrid e in clu sio n s are n eve r fo u n d seg rega te d in gro u p s or stre a k s, as are a lu m in a and silicate s, b u t are a lw a y s v e r y sm all, scarce, an d th in ly sc a tte re d , th e ir w e a k e n in g effe ct on th e m etal is p r a c tic a lly n egligib le. T h e y h a v e been fo u n d in tita n iu m -tre a te d steel a xles as w ell as rails b u t n ot in steel castin g s nor so ft steels, w here sm aller a m o u n ts of tita n iu m h a ve been used.
F i c . 15—S u i . f i d k S e g r e g a t i o n i n U n t r e a t e d R a i l X 200 F i g . 16—S u l f i d e s i n T i t a n i u m - T r e a t e d R a i l X 200
R ed u ced b y O n e-eighth R ed u c e d b y O ne-eig h th
Inclusions in a cross section of th e web. A g ro u p like th is w ould T y p ical inclusions w ith o ne sm all d a rk slag inclusion (rig h t), a p p e a r as a p u re black sp o t on a su lfu r p rin t. N o t etched. T h is show s th e d irtie s t s p o t found in th e cross section of th e web of a
tre a te d rail. N o t etch ed .
F i g . 17—B a d l y S e g r e g a t e d U n t r e a t e d R a i l X 100 R ed u c e d by O n e -tw e n tie th
Cross section of th e u p p e r p a r t of th e web showing v e ry b rittle s tru c tu re .; T h e d a rk c o n stitu e n t is cem en tite or iro n - and carb id e an d th e lig h t c o n stitu e n t is p earlite. E tc h e d w ith b o iling acid alkaline sodium picrate.
ference in nitrogen co n te n t of th e m etal m a y be due m erely to th e lo ckin g up of som e n itrogen b y tita n iu m in th e p in k inclusions, or also p a r tly to th e a c tu a l re m oval of n itrogen from th e liq u id steel b a th . A t a n y rate, if it is assum ed th a t n itrogen has an in ju rio u s effect on steel, th e lo w er a m o u n t fo u n d b y a n a lysis m ust be an a d v a n ta g e , for ev en if th e w hole a m o u n t rem oved from th e m etal itse lf is still presen t in th e p in k inclusions, it could h a v e no m ore ill e ffe ct in
F i g . 1 8 — T y p i c a l T i t a n i u m - T r e a t e d R a i l X 4 0 0 R ed u c e d b y O n e -tw e n tie th
C e n te r of h ead , show ing n o rm a l s tru c tu re : la m in a te d p e arlite , so rb ite , considerable ferrite, w ith a few g ra y sulfide globules. E tc h e d w ith p ic ric
(B essem er steel.)
I t is an u n fo rtu n a te fa c t th a t som e so -ca lled “ ti
ta n iu m -tre a te d ” steels h a v e n o t b een a n y b e tte r in regard to seg rega tio n th a n th e a v e ra g e u n tre a te d steel.
T h ese h a v e c o n s titu te d , h o w e ver, an in s ig n ifica n t
p ercen ta ge of th e to t a l n u m b er ex a m in ed in ou r la b
o ratories. In e v e r y case th e se se g re g a te d “ t r e a te d ”
rails h a v e n o t sho w n a tita n iu m c o n te n t of o v e r 0.005
per cen t (th e a v e ra g e tr e a te d rails are w ell a b o v e th is
figure) and th e p in k n itrid e in clu sion s h a v e also been
F eb . , 1915 T H E J O U R N A L O F I N D U S T R I A L A N D E N G I N E E R I N G C H E M I S T R Y 93 a b s e n t fro m th e m . T h ese fa cts in d icate th a t n ot
e n o u g h tita n iu m w as a c tu a lly ad ded in th ese h eats t o p ro d u ce th e u su al effects; eith er th e h eats w ere b a d ly oxid ized , and n eeded m ore th a n th e usual a m o u n t of tita n iu m , or som e of th e a llo y w as lo st or w asted in th e slag. I t is w ell know n th a t ch em ical reactio n s do n o t in m ost cases proceed ra p id ly to com p letio n w hen o n ly th e th e o re tica l am ou nt of reagen t is a p plied, b u t an excess of greater or less am o u n t is u su a lly needed. In th e case of deoxidation of steel w ith tita n iu m , th e excess n ecessary is p ro b ab ly a t least 0.005 Per cen t, w h ich , it w ill be a d m itted , is a v e ry sm all am o u n t.
H a v in g n ow exp lain ed th e reasons for th e ad ditio n of tita n iu m to steel, an d its general effects thereon, it m a y be of in te re st to giv e some concrete exam ples of th e im p ro v e m e n t, show n b y te stin g
m ach in es an d in a ctu al service, of ti- ta n iu m -tre a te d steel as com pared w ith plain u n tre a te d steel of th e sam e general com p o sition. I t m ust be em phasized again th a t as th e am ou nts of tita n iu m found in tr e a te d steels are en tirely n eg li
gible, so no ch an ge in m icrostructure of th e steel is caused b y it, and the p h ysica l p ro p erties are no b etter th an are th e o re tic a lly possible w ith p e rfe ctly clean and so u n d steel of th e given com position. O ur m ost com plete know ledge on th is su b je c t h as been acquired w ith rail steel, and fo rty -tw o sam ples of plain and tre a te d O pen-H earth steel rails h ave been e x h a u s tiv e ly tested , p h ysica lly and ch e m ica lly , in our laboratories. For th is p u rp o se th e sam ples h ave all been taken fro m th e “ A rails,” or first rails rolled fro m th e ingots, after the usual discards fro m th e ir top s, th u s rep resent
ing in each case m etal from th e top p a rt of an in g o t, w hich w ould show th e greatest am o u n t of segregatio n and im purities.
T h e “ A ” rails fro m w hich sam ples were to be ta k e n w ere chosen a t random from th e p ro d u cts of vario u s m ills and a t d ifferen t tim es b y th e m an u factu re r’s
or th e p u rch asin g railro ad ’s rep resen tatives, b u t th e sam ples w ere a lw a y s ta k e n in pairs, one tre a te d and one u n tre a te d fro m each rolling, so th a t, in th e final co m p arison th e influence of th e conditions of m an u factu re co u ld be as fa r as possible elim inated. A ll sam ples s u b m itte d w ere te ste d im p a rtially, w ith th e sam e care an d b y th e sam e m ethods, and th e results h a v e been p u b lish ed in our R a il R e p o rt B u lletin s. T h e final a v e ra g e s o f all th e results are given on p ag e 94.
C h e m ic a l a n a lyse s were m ade a t four places on each rail: to p of head, cen ter of head, w eb, and flange.
T h e lo w e st and h igh est figures for each rail were a v e ra g e d , g iv in g th e a verage low and high results here rep o rte d .
T h e L a n d g ra f-T u rn e r endurance m achine bends a th in te s t-b a r b a c k w a rd and forw ard th ro u g h a sm all an gle b y q u ic k ly a lte rn a tin g blow s, and th e results
are exp ressed as a lte rn a tio n s en d u re d before- fractu re.
T h e stresses ap p lied to th e te st-p ie ce are a b o v e its ela stic lim it.
T h e W h ite -S o u th e r en d u ran ce m ach in e holds a te st-b a r in th e m id d le, tu rn in g it v e r y fa s t lik e an axle, w hile w eig h ts are su sp en ded fro m its ends. T h e stresses a p p lied are b elo w th e ela stic lim it, and th e failu re is th u s due to fa tig u e . T h e resu lts are exp ressed as re v o lu tio n s en d u red , b u t m a n y te st-b a rs w ere re m oved u n b ro k en a fte r th ir t y or f o r t y m illion re v o lu tion s.
A s th e a b o v e figures rep resen t te sts on tw e n ty -o n e u n tre a te d rails, an d tw e n ty -o n e tr e a te d rails, w ith all oth er con d itio n s k e p t as n e a rly a lik e as po ssible, it is b elieve d th a t th e y possess real v a lu e fo r sh o w in g th e im p ro ve m e n t to be e x p e cte d in “ A ” rails w h en p ro p e rly
F i g . 1 9 — T y p i c a l T i t a n i u m - T r e a t e d R a i l X 4 0 0 : N o t R e d u c e d
C e n te r of h ead show ing n o rm al s tru c tu re : la m in a te d p e arlite , so rb ite , a n d tra c e s of ferrite. E tc h e d w ith picric acid. (O p e n -H e arth steel.)
trea ted w ith tita n iu m . T h e im p ro v e m e n t in oth er rails, from lo w er p o sitio n s in th e in go ts, w o u ld be m uch less m arked, b u t th e rails th a t g iv e m ost of th e tro u b le in service are th e seg reg a te d “ A ” rails; th e se are rendered p r a c tic a lly as u n ifo rm and h om o gen eo u s as oth er rails b y tr e a tm e n t w ith tita n iu m . T ita n iu m - tre a te d rails are n o t b e tte r, p ro b a b ly , th a n th e b est possible u n tre a te d rail, b u t b y th is tr e a tm e n t th e general sta n d a rd of q u a lity is u n q u e s tio n a b ly raised, u n ifo rm ity is m ore n e a rly a tta in e d , an d th e b ad h eats of d an gero u sly seg rega te d or d ir t y ste el are a vo id ed .
In order to acq u ire still m ore p o s itiv e d a ta on th e effect of tita n iu m on se g reg a tio n in rails, se v e n ty -n in e
“ A ” rails fro m d ifferen t u n tre ate d h e a ts and th irty -o n e
sim ilar rails from d ifferen t tre a te d h e a ts w ere e x a m in e d '
re ce n tly b y m eans of su lfu r p rin ts an d ch em ical
a n a lyse s fo r carbo n m ade on each a t an u p p e r corn er
94
T H E J O U R N A L O F I N D U S T R I A L A N D E N G I N E E R I N G C H E M I S T R Y Vol . 7, N o . 2 of th e hea'd and a t th e ju n ctio n of h ead and web.
T h e a ve ra g e difference betw een these tw o p rin ts w as 17 per cen t for th e u n tre ated rails, and th e w orst rail show ed 40 per cen t, w hile on ly 29 of these 79 rails show ed less th an 12 per cent. F o r the tre a te d rails the a vera ge difference w as 3.1 per cen t, and th e w o rst one g a v e 11.5 per cen t, none of th e 31 show ing o ver th is am ount.
Ch e m i c a l An a l y s e s Un t r e a t e d Ra i l s Tr e a t e d Ra i l s
Pe r c e n t a g e s Lo w Hi g h Lo w Hi g h
C a rb o n ... 0 .5 8 0 .8 2 0 .6 3 0 .7 6 M an g an ese... 0.71 0 .7 8 0 .7 5 0 .7 9 P h o sp h o ru s... 0 .0 1 6 0 .0 2 6 0 .0 1 8 0 .0 2 3 S u lfu r... 0 .0 3 2 0 .0 5 8 0.0 3 1 0 .0 4 0 S ilicon... 0.1 1 7 0.131 0 .0 9 0 0 .0 9 9
Un t r e a t e d Ra i l s Tr e a t e d Ra i l s
Te n s i l e Te s t s He a d Fl a n g e He a d Fl a n g e
E lastic lim it... 56,071 55,961 5 9 ,7 3 8 6 0 ,3 3 8 U ltim ate s tre n g th ... 118,138 119,385 124,857 125,690 E longation, p er c e n t... 12.8 1 5.4 13.1 14.4
R ed u ctio n of area, p er c e n t 14.3 18.5 15 .4 18 .2
Un t r e a t e d Ra i l s Tr e a t e d Ra i l s
H ead W eb F lan g e H e ad W eb F lan g e W h ite-S o u tlier... 16,550,920 23,923,628
Brincll h a rd n e ss 220 248 216 226 235 227
Im p a c t re sista n c e s 1 - 47 1 .08 1.23 1 .5 8 1.21 1.43 E n d u ran ce
L a n d g ra f- T u rn e r.... 1312 1001 1324 1280 1084 1270
T h e im p a ct resistan ces were m easu red w ith a F re m o n t m achine, and are exp ressed as k ilo gram -m eters ex
pended in b re ak in g a te st-p iece 7 b y 10 m m . in cross- section.
T h e railroads h a v e been a cq u irin g d a ta for som e tim e in regard to th e w ear of tita n iu m -tre a te d rails in tra c k , as com pared to th a t of o rd in a ry O p en -H earth rails.
T h e results h a ve been u n ifo rm ly fa v o ra b le to th e trea ted rails, in som e cases v e r y d ecid e d ly so. F o r instan ce, on a sharp cu rv e on th e B o sto n E le v a te d R a ilw a y , tita n iu m -tre a te d rails laid a lte rn a te ly w ith plain rails of p ra c tic a lly th e sam e com p o sition show ed 41 per cen t less w ea r a fte r 214 d a y s ’ s e rv ic e . In a te s t m ade b y th e R o c k Is la n d R a ilro a d , tita n iu m -tr e a te d rails in 17 m on ths h a d 0.014 sq. in. a b ra d e d fro m th e ir sectio n s, on th e a v e ra g e , w hile e le c tric ste el ra ils sh o w ed u nder th e sam e c o n d itio n s a loss o f 0.058 sq. in ., and o rd in a ry rails 0.075 scl- in- O th e r in stan ces of th e sam e general ty p e m igh t also be g iv en , b u t enough has su rely been said to show c le a rly th e a d v a n ta g e s follow in g th e use of tita n iu m in rail steel.
In axle steel it has been fou n d sim ilarly a d v a n ta g e o u s to use tita n iu m for p u rify in g th e m etal and p re v e n tin g segregation . In steel castin gs th e use of tita n iu m as a deoxidizer has u su a lly been su ccessfu l' and sa tis fa c to ry , and in so ft steel for p lates an d th in sheets m uch tita n iu m is used. T h is elem ent is p referred to a n y oth er d eoxid izer becau se it does n ot le a v e a n y p ro d u ct of its o x id atio n in th e steel as do alu m in u m and silicon, and th e in g o ts th erefo re roll o u t sm o o th er and th e finished sh eets h a ve a b e tte r su rface. S m all d efe cts on th e su rface of a sh eet are v e r y serious in g a lv a n iz in g , so th a t th e sm oother su rface of tita n iu m -tre a te d s h e e ts, due to cleaner in gots, is m uch a p p reciated .
A fe w ph o to m icro grap h s an d su lfu r p rin ts are su b m itte d to illu stra te som e o f th e p o ints m en tio n ed in this paper, th o u gh of course th e y are n o t in te n d e d to prove m uch in th em selves, b u t m erely to serve as illustration s. I t is h azard o u s to d raw conclusion s from tw o or th ree trials or instan ces, b u t an a ve ra g e from fo r ty or e ig h ty te sts sh o u ld su rely be tr u s tw o r th y .
Ph y s i c a l Te s t i n g La b o r a t o r y Ti t a n i u m Al l o y Ma n u f a c t u r i n g Co m p a n y
Ni a g a r a Fa l l s, Ne w Yo r k
M A N G A N E S E S T E E L 1 B y J o h n H . H a l l
C O M P O S IT IO N A N D C H A R A C T E R IS T IC S
M an gan e se steel w as d isco ve red in th e e a r ly eigh ties, and since th a t tim e has fo u n d a p lace fo r its e lf w h e re v e r a steel is requ ired th a t is h ig h ly re sista n t to w ear.
In th e origin al exp erim en ts, th e steel w as m ade b y m ixin g m olten ferro m an gan ese and carbo n less B essem er b lo w n m etal in such a m o u n ts as t<? g iv e v a rio u s p ro p o rtio n s of m an gan ese in th e finish ed p ro d u c t; as a consequ ence th e ra tio of th e m an gan ese to th e carb o n w as p r a c tic a lly fixed, th e carb o n co n te n t d ecreasin g as th e m an gan ese w as dim inish ed. W ith less th a n a certain a m o u n t of m an gan ese, th e m etal p ro v e d to be e x tre m e ly b rittle , and in p ra ctice th e m an g an ese w as seldom less th a n 9 per cen t, th e steel as g e n e ra lly m ade co n tain in g fro m 10 to 14 per cen t m an gan ese and from 1 to 1.5 per cen t carbo n . T h e silico n is g e n e ra lly fro m 0.2 to 0.5 per cen t, th e su lfu r a lw a y s v e r y low (a b o u t 0.001 per ce n t), th e p h osp h o ru s ave ra ge s from 0.08 to 0.1 per cen t. S m all v a ria tio n s in th e silicon and p h osp h o ru s h a v e little effe ct on th e prop erties of th e ste el. T h e su lfu r is in v a r ia b ly low , becau se th e m an gan ese of th e steel elim in a te s it b y
flo ta tio n as M n S . B y h e a tin g th is ste el to b e tw e e n 1000 and i i o o 0 C ., it can be m ade, if n ot of to o h e a v y a sectio n , to con sist e n tire ly o f th e m e ta llo g ra p h ic c o n s titu e n t k n o w n as a u sten ite.
M o re recen t researches, in som e of w h ich th e a u th o r h as p a rticip a te d , h a v e sh o w n th a t if th e carb o n co n te n t of th e m etal is m a in ta in e d a t a b o u t 1 p e r ce n t, th e steel w ill be a u sten itic a fte r q u en ch in g, ev en if th e m angan ese co n te n t is as lo w as 5 per cen t or e v e n a little less, th e ran ge o f carb o n co n te n t w ith in w h ich pure au sten ite can be o b ta in e d b ein g n arro w w ith lo w m angan ese co n ten t, a n d w id en in g as th e m an g an ese co n te n t increases. T h is can be m ore re a d ily u n d e r
sto o d ^by referen ce to th e a cc o m p a n y in g d iag ram sh o w in g p a rt of th e m an gan ese ste el series, in w hich th e carbo n co n te n t is p lo tte d as ab scissa and th e m angan ese co n ten t as o rd in a te . W ith in th e area W X Y Z th e ste el con sists of p u re a u ste n ite w hen qu en ch ed. S teels im m e d ia te ly to th e le ft o f th e line C = 1-075-0.04 M n are m ore or less m a rte n sitic w h en q u en ch ed ; steel im m e d ia te ly to th e rig h t o f th e line C = 1.075 + 0.1/3 M n c o n tain free ce m e n tite
* P re s e n te d before th e N ew Y o rk Sectio n of th e Society of C h em ical In d u s try . C h em ists’ C lub. N o v e m b er 20, 1914.
F e b . , 1 9 1 5 T H E J O U R N A L O F I N D U S T R I A L A N D E N G I N E E R I N G C H E M I S T R Y
95 w hen q u en ch ed , th e a m o u n t of cem en tite increasing
as th e carb o n co n te n t rises. T h is is also tru e of th e p rolon gation s of th e lines for a certain d istance.
T h ese lin es w ere p lo tte d as th e resu lt of a carefu l re search h a v in g for its o b je ct th e d eterm in atio n o f th e useful ran ge o f m angan ese co n ten t in th ese steels.
T h e line A B rep resents, w ith no pretense a t accu racy , th e co n ten ts of carb o n and of m anganese of th e steels form ing th e basis o f th e origin al d isco ve ry and p a te n t.
T h e reason w h y th e steel w as fou n d to be m arte n sitic and b rittle w h en th e m anganese w as still "com p ara
t iv e ly high , is a p p a re n t a t a glance. T h e w ell-know n d iagram of G u ille t, sh o w in g th e m icrostru ctu re of th e steels of th e iron-carbo n-m angan ese series, is not p arallel to th is d iagram , as G u ille t’s figure represents th e steel in th e norm alized condition, w hereas in th is figure, th e stru ctu re s are those of th e steel in th e quenched s ta te .
P R O P E R T I E S O F T H E S T E E L
M an ganese steel has a v e ry low c o n d u c tiv ity for both h eat and electric cu rren t, a low m eltin g p o in t (some 1,360° C .), a v e ry high coefficient of expan sion (m aking n ecessary a sh rinkage allow an ce of s/it inch to th e fo o t in fo u n d ry w ork), and is p ra c tic a lly n o n m agn etic in all o rd in ary conditions. In th e cast state it is v e r y b rittle . T h e cast m aterial a fte r h ea tin g to 10 0 0 -110 0 ° C . an d quenching has o n ly a m o d e ra te ly high ten sile stre n g th , a b o u t 60,000 to 80,000 lbs. per sq. in., a ra th e r lo w elastic lim it in both tension and com pression, an d a rath er high d u c tility ; its sh earing stren gth is r e m a rk a b ly high. W hen rolled or forged and tre a te d , th e ten sile stren gth is in creased v e ry g re a tly , som etim es reach in g 150,000 lbs. per sq. in., and th e d u c tilit y m uch im p roved ; th e oth er prop erties are n o t m uch altered . T h e rolled m a terial, if un
tre a te d , is q u ite b rittle .
T h e ch ief ch a ra cte ristic to w hich th e m etal ow es its usefu ln ess is its hardness. In th e tre a te d s ta te in w h ich th e steel has to be used, th is h ardness is of a p e cu lia r k in d , inasm u ch as hardness te sts w h ich de
pend u p o n in d e n tin g th e m aterial do n ot g iv e a high figu re fo r th is steel— in fa c t it can be m ade to peen or flow in th e cold under th e blow s o f a ham m er, to a co n sid e rab le e x te n t. In a w a y, th erefore, th e steel is so ft; th is is due to its low elastic lim it. B u t, unless s p e c ia lly h e a t-tre a te d , it can not be c u t w ith to o ls to a su fficien t e x te n t to m ake m achining p ra ctica b le , and its resista n ce to m ost kinds of w ear is e x tra o rd in ary .
A s th e m angan ese conten t is reduced, if th e carbon is k e p t a t th e prop er figures, th e properties chan ge m u ch less th a n w as o rigin ally supposed. T h e stren gth fa lls off a little , th e tou ghness dim inishes p ro g re ssive ly, a n d th e m agn etism increases a little . T h e resistance to w ear, h o w e ver, is v e ry little altered as lon g as th e m an gan ese is k e p t a b o v e abou t 5 or 6 per cen t, and th e te n d e n c y to peen or flow decreases as th e m anganese c o n te n t dim inishes. T h e usefulness of th ese low m an gan ese steels is, h ow ever, lim ited to a rath er n arro w field b y th e ir co m p arative la c k of tou gh n ess;
th e y are n o t e x tre m e ly b rittle , like th e m arte n sitic steels of th e sam e m anganese co n ten t, b u t th e y are
n ot a t all as to u g h as th e steels co n ta in in g o v er 10 per cen t of m angan ese.
U S E S
