SYSTEM.1

Through the kindness of Dr. C. Travis =indersen of the U. S. Bureau of. Mines, we were supplied with alloys made up from electrolytic manganese and ot...
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JACK Rf. PAUL A N D G. V. B E A R D

LIQUIDUSSOLIDCS POISTS OF T H E 1IASGXSESE-SICKEL

SYSTEM.1 JACK 31. PAUL

AND

G. V. BEARD

Department of Chemistry, Z'niversity of I'tah, Salt Lake C i t y , C'tah Received August 12, 194Y

This investigation was undertaken because of the currently enhanced interest in manganese, and because of the scarcity of reliable data concerning it and its alloys. Through the kindness of Dr. C. Travis =indersen of the U. S. Bureau of Mines, we were supplied with alloys made up from electrolytic manganese and other pure metals, in the present case manganese and nickel only. The alloys were melted in an electrical resistance furnace designed for the purpose.* The crucibles in xhich the melting and cooling of the alloy. were carried out Tvere made from granular alundum, the interior of the crucibles being 10 mm. wide by 45 mm. deep. Temperature meawrements n-ere made by means of a thermocouple of S o . 22 B & S chrome1 and alumel wires. The furnace was very carefully broken in by slowly increasing the current in small incrementp, and in all runs the temperature \\-as gradually raised t o the desired range over a period of several hours. The samples for the most part were prepared in rods in. in diameter, and about 1 in. of such a rod n-as used as an individual sample. In order to prevent oxidation the samples w r e placed in the alundum sample container ( Q in. in4de diameter and I$ in. deep) only after the furnace temperature n-as considerably over the estimated melting point of the sample. -4s soon as the samples had been in the furnace long enough to reach furnace temperature, the alundum-covered thermocouple was pushed into the sample, and the current through the furnace was decreased to 2.5-3 amp. as a base Jvhich x a s held constant while the readings irere being taken. This procedure was adopted to prevent too rapid cooling of the samples. soon as the temperature started to fall, the voltage generated in the thermocouple was accurately measured and recorded every half-minute. The Bureau of Standards' conversion table for chromel-alumel thermocouples n-as used to find the temperature corresponding to each millivolt reading, and cooling curves were plotted with data so obtained. Xt the end of each run the standard cell was again used to check the Edison cell to be certain that it had remained constant, After each run the thermocouple was cut off and a new junction Tvas prepared and covered with alundum as before. RESULTS

The cooling curve shown in figure 1 was obtained from a run on an alloy containing 70 per cent manganese and 30 per cent nickel, and was one of the better curves obtained. 1 Contribution S o . i 5 from the Chemical Laboratories of the Kniversity of Utah. investigation was carried out from October 1941 until April 1942. * The details of this furnace will be supplied t o anyone upon request.

This

M.4XG.4SESE-KICKEL

STSTEM

751

Runs were made on several alloys with the results given in table 1. The temperature-composition diagram is shown in figure 2. The manganese and nickel used in these results were of high purity; both were electrolytic and ran about 99.8 per cent by standard methods of analysis. S o t

FIG. 1. Cooling curves for 70 per cent manganese30 per cent nickel alloy

all samples were analyzed at the end of the experiment, but those analyzed indicated practically no contamination or oxide formation. It is believed that our manganese samples are purer than those used by other investigators (1, 2, 3), although not all the articles referred to are available a t this institution.

T.1BLE 1

1

hill

Ti

per cenl

per w t i i

35 40

52.5 5i.5 62.: 65 70

35 30 ‘‘5 20

I 3

so

Ponr

“C.

1123 1079 1089 105s 1046 1030 1011 1006 LIelting point = 1006 JIelting point = 1005 1012 1005 1022 1040 1066 1040 1105 1058

37.3

--

>OLDUS

“C.

65 60 55 47.5 42.5

45

~

LIQUIDUS POINT

-~

I

20

30

I

I

I

40

4-0

60

Composftion

% N/

FIG.2 . Temperature-composition diagram for t h e manganese-nickel system 752

70

V.LI I T T WITH C O M P O S I T I O S

('honical Aibstracts does not give IIY this information. agreement I\ ith the re-ulth puhli-lied by 11. I-Iansen ( 3 ) .

7 53

Our work i5 in fnir

SVMbl LRT

'I'he liquidus-solidus points of manganese-nickel alloys from 35 per cent manganese45 per cent nickel to 80 per cent manganese-20 per cent nickel h a w been determined. REFEREXCES (11 SHEVTSHLSBIII, S.F., I7n.4sm. G. G., ~ S DRIKOWSKOW, A . E. J. Russ. Phys Chem. SOC. 7, 1051 (1906); 39, 787-802 (1908). (2) DOT-RDISE, A. D: Rev. soc r u s e de metall. 1, 11-23, 341-95 (1912), Rev. met. 29, 56553 (1932). (3) HASSEN, 11 . A u j h a u der Zrc eisto~~i7ellzeruiiqen.

'I"E J7lXY)S1'l3- OF SOLUTIOSS OF L'13111aIR\7 hLCIOHOLS XSD FAITTI--IC'IDS IS HESZESE XSTI IS C'ARBOS TETRAICHLORIL)E Vi'. J . JOSES, S. T.BOWDES, W .K. IARSOLD,A N D W. H . JOKES

T a t e m Laboratories, Cnivemify College, Cardiff, W a l e s

Received May 28, 1941 ISTRODI-CTIOS

'l'lie viscosity of solutions of ethyl alcohol and acetic x i d in benzene has heen investigated by Dunstan (9) antl by 1liichin (21), of solutions of ,ti-propyl alcohol in benzenc by Dunstan antl Iiy Spells ( 2 - l ) ,and of solutions of cert'ain butmyland itniyl alcohols, other than ?z-hutyl and Ti-amyl, in benzene by Muchin and by Spells. Dunstan found thxt :it 25°C'. in benzene ethyl alcohol gave a minimum T-isrobity at C, per cent of tlic alcaohol, propyl alcohol a t 5 per cent of the alcohol, tint1 acetic acid at 11 per cent of the acid. Findlay (10) determined the yiscosity 0 : ' solutions of methyl nntl ethyl nlcoholx in benzene, and of ethyl alcohol in c:irbon tetrarhloricle, at thc hoiling point of the solutions, and found masimn in the first antl third systems, Init not with ethyl alcohol in hcnzene. Staudinger ~iiitlOchiai ( 2 5 ) inr-estigatecl the viscosity of dilutc solutions of the fatty acids from ti-caprylic acid to cerotic. acid in cai4xni tc.trachloride a t 20°C. and observed that the viscosity incrtmed proportionally to the chain length of the acid. The present \\-ark \vas undertaken for the purpose of finding how viscosity varied ivith composition for thc 1vhole range of solutions from one pure component to the other at 25Y'. in hinary ,terns of nlcoliols and lwnzcne, fatty acids and Iwizene, alcohols nntl rarhon tetrachloride, und fatty acids and carbon tetrachloride; in particular, it \vas sought t o ascertain hoiv the posit.ions of minima of i-iscwity shifted as the homologous serks of alcohols and ac%k were ascended.