COMPOSITIONAL DEPENDENCE OF M_s TEMPERATURES IN HIGH-PURITY IRON-CHROMIUM-NICKEL AUSTENITIC ALLOYS

Abstract

The onset of martensitic transformation on cooling has been studied in high-purity Fe-14 to 20 wt % Cr -8 to 25 wt % Ni austenitic alloys. In samples with Fe < 72 %, extensive transformation takes place below Ms according to the sequence γ → ε → α'. In samples with Fe > 72 %, α'-formation occurs in two successive stages ; possible transformation models are considered. No unique formula relating Ms to composition is applicable to the whole composition range studied