Activities of Manganese and Silicon in δ-Iron at Solid-Liquid Equilibrium Temperature

Abstract

The equilibrium relationship between solid and liquid has been studied for Fe-Mn-Si ternary system.
The solid-1iquid equilibrium temperature can be related to the concentrations of Mn and Si in liquid iron alloy as follows:
From measured solid-liquid equilibrium distribution ratio, the activity coefficients of Mn and Si in δ-iron are calculated. The results obtained are as follows:
where pure solid Mn and Si are taken as the standard states.
Using these results, the composition of δ-iron in equilibrium with liquid Fe-Mn-Si alloy can be calculated.
T=t_e+273
[% i (S) ]: Weight percentage of component i in solid phase (δ-iron)
[% i (l) ]: Weight percentage of component i in liquid phase