1970 年 56 巻 12 号 p. 1467-1476
An investigation was carried out to know the effect of alloying elements on the solubility of sulphur and to determine the interaction coefficients of sulphur in 5-iron. The solubility of sulphur was determined by using the solid-liquid equilibrium technique presented in the previous work.
The crucible assembly was lowered very slowly in purified argon gas in Tamman furnace, so that equilibrium between solid and liquid iron was attained.
The relation between the partition ratio of sulphur in Fe-S system (Ls′) and in Fe-S-X system (Ls) is
log Ls=log Ls′+log(f(X)l/f(X)S)
where ƒs(X) and ƒl(X) are the interaction coefficients in solid and liquid iron respectively. By using the relation, the interaction coefficients of various elements in solid iron obtained are as follows:
log f(Mn)S=-0.58[% Mn] <0.15% Mn
log f(Si)S=-0.286[% Si] <0.4% Si
log f(O)S=-37.4[% O] <0.007% O
log f(C)S=7.29[% C] <0.03% C