Interaction coefficients in the iron-carbon-titanium and titanium-silver systems
- PDF / 434,444 Bytes
- 5 Pages / 603.28 x 783.28 pts Page_size
- 11 Downloads / 157 Views
pT, = 0.32,
~TCi= --11.94,
pTi,c = - 9 . 9 6
pC = - 4 . 5 2 ,
An experimental study has been made of the distribution of titanium between liquid silver and liquid iron at 1600 ~ By the use of the interaction coefficients of titanium and r~ in liquid iron, the thermodynamic parameters of titanium in liquid silver were determined as (rOi)Ag
I.
=
2.44 X 10 -3,
Ti (gT1)Ag = --6.17,
INTRODUCTION
THE solute
activity interaction coefficient is one of the bases of melt thermodynamics. Since Wagner, tl] Chipman, t21 and Sherman and Chipman t31 proposed the concept of an activity interaction coefficient between components, many studies were done to determine the interaction coefficients, and the results obtained were published in the literature. [4-7] But not all of the systems were studied completely. For some systems, there were only a few studies done, and for others, the results obtained did not agree with each other well. For example, there have been a great number of studies done about the solubilities of titanium and carbon and r ~ in the FeC-Ti system L8-131 but few about the interaction coefficients of carbon on titanium, u~ The second-order interaction coefficients, pTCi ano. PTI T,,C, in particular, have not been reported in any published literature. Also, there are no published data of the thermodynamic parameters of titanium in liquid silver at 1600 ~ The distribution law (between the liquid iron and liquid silver) method was initially used by Chipman t151 in 1934 to study the melt thermodynamics. In his experiment, electrolytic iron and a pure grade of aluminum and silver were melted together at 1600 ~ With the chemical analysis data of aluminum in both the iron and silver layers, the activity of aluminum in liquid iron was determined. Since then, this method has been applied to several systems. [16-191 In the present work, by the use of the interaction coefficients of titanium in liquid iron, the distribution law method was applied to determine the selfinteraction coefficients of titanium and r ~ in liquid silver at 1600 ~ In 1964, Schroeder and Chipman t2~ developed the distribution law method into the ternary silver bath isoactivity method and used it to study the Fe-C-Si system,
GUO YUANCHANG, Teaching Assistant, WANG CHANGZHEN, Professor, and YU HUALONG, Engineer, are with the Department of Metallurgical Physicochemistry, Northeast University of Technology, Shenyang, Liaoning, People's Republic of China. Manuscript submitted December 22, 1988. METALLURGICAL TRANSACTIONS B
( P T T, i)Ag
=
16.3
in which iron and carbon are not dissolvable in liquid silver. Several Fe-C-Si alloy samples with different carbon concentrations were held in contact with the same silver bath, and by the silicon's movement, the iso-siliconactivity state among samples was attained, from which the interaction coefficients of carbon on silicon in liquid iron were calculated at 1420 ~ Following Schroeder and Chipman, some researchers used this method to study other systems, f2L221 In this work, seven Fe-C-Ti alloy sample
Data Loading...
