Experimental and thermodynamic study of nickel (30 wt.%Cr) – based alloys containing between 2.5 and 5.0 wt.% carbon

Abstract

AbstractSix {Ni-30 wt.% Cr}-based alloys containing from 2.5 to 5 wt.% C, were elaborated by casting and heat treated at 1000, 1100, and 1200°C for 50 h to achieve stabilization. Their melting ranges and the phase surface fractions were established. These results were compared to thermodynamic calculations. All microstructures are hyper-eutectic and carbides are either Cr7C3 or Cr3C2. The carbide fraction increases with the carbon content and graphite appears for carbon contents higher than 4 wt.% C. The experimental solidus and liquidus temperatures are several tens of degrees lower than the calculated ones but their evolution versus the carbon content are well represented by calculations. There is a good agreement between experiments and calculations concerning graphite. The hardness is about 300 HV and decreases when the heat-treatment temperature increases.