Densification, microstructure and mechanical properties of spark plasma sintered Ni-17%Cr binary alloys

Spark plasma sintering (SPS) system was used to develop Ni-17%Cr alloys using nickel and chromium as the raw elemental materials. The powders were fabricated at different sintering temperatures ranging between 800 and 1100 °C, at constant pressure of 50 MPa, heating rate of 150 °C/min and holding time of 10 min. Scanning electron microscopy (SEM), X-ray diffraction (XRD), Vickers microhardness tester and Archimedes’ method were used to investigate the effect of sintering temperature on its microstructure, phases, mechanical properties, densification and fracture mode. The results showed that the relative density, microhardness and fracture morphology of the alloy were affected by sintering temperature, which also affects the microstructure. The maximum relative density of 98.2% and hardness value of 296.33 HV _1.0 were obtained at sintering temperature of 1100 °C. The fractography results revealed that the sintered alloys were characterized by transgranular fracture from 900 to 1100 °C.