Deoxidation Equilibrium of Chromium Stainless Steel with Si at the Temperatures from 1 823 to 1 923 K

Abstract

The deoxidation equilibrium of chromium stainless steel with silicon was studied up to 25 mass% chromium at the temperatures of 1823, 1873 and 1923 K, in order to clarify the effect of chromium on silicon deoxidation of liquid iron–chromium alloys. Results obtained were summarized as follows

SiO₂(s)=Si+2O
log K_Si(=a_Si · a_O²/a_SiO2) = –24600/T+8.40
log f_Si^Cr = –0.021[%Cr]+4.3×10^–4[%Cr]², [mass%Cr]≤25, 1823≤T≤1923 K

The phase stability diagrams of Si–Al complex deoxidation was estimated at [mass%Cr]=0, 13, 20 and 1823 K, by applying present results and recent data assesed by one of authors for Cr- and Al-deoxidation equilibria in liquid iron.