2011 Volume 52 Issue 12 Pages 2155-2158
Diffusion-couples of pure Fe/Fe-40 at%Cr alloy were used to analyze the phase separation process in Fe-Cr alloys. Diffusion-couples were solution treated at 1050°C for 3.6 ks and subsequently aged at 500°C for 3.6–3600 ks. Interdiffusion zones were analyzed by HR-TEM and hardness measurements. The EDS-SEM analysis of solution treated, water-quenched and then aged diffusion-couple permitted to obtain the equilibrium composition of miscibility gap at 500°C to be 14 at% Cr. The HR-TEM analysis of the aged diffusion-couple showed the change in size and volume percentages of precipitates with composition. The hardness measurements of the aged diffusion-couple indicated the age hardening due to the presence of nanometric Cr-rich precipitates in a Fe-rich matrix.
