Investigation on creep deformation of two high entropy alloys

摘要

The current paper investigates the creep deformation of two kinds of high entropy alloys: Al0.15CoCrFeNi and Al0.6CoCrFeNi alloys by means of stress relaxation test.From metallurgical analysis, it is shown that the alloys have typical simple FCC solid solution structure for Al0.15CoCrFeNi and FCC+BCC structure for Al0.6CoCrFeNi alloy, which are similar to those of high entropy alloys.According to the relationship between stress and creep rate of the alloys, it follows Norton's power law at the temperature of 580-700 ℃.The activation energies of Al0.15CoCrFeNi and Al0.6CoCrFeNi alloys were in the range of 365-376 kJ mol-1 and 255-280 kJ mol-1, respectively.It is supposed that higher creep rate and lower activation energy attributes to the finer grain size of Al0.6CoCrFeNi alloy.