Densification of Ni-20Cr alloy course-powder by pulse current pressure sintering

Using pulse current pressure sintering, the densification behavior of Ni-20Cr alloy powder, 70 mum average particle diameter, was investigated via microstructural observations and by kinetic analysis of the densification rate. Observation of the microstructures revealed that the neck radii were very small. Recrystallization and melting at the grain interface did not occur. Densification rates calculated by a model that assumed steady-state creep were consistent with the experimental results. Creep rates obtained from the model calculation agreed with previously reported values. Densification of Ni-20Cr alloy powder by pulse current pressure sintering was rate-controlled by steady state creep. The pulse current affected the densification by increasing the macroscopic temperature of the sample.