Cr 3 C 2 –20%Ni cermets prepared by high energy milling and reactive sintering,and their mechanical properties

Abstract

Cr₃C₂–20%Ni cermets were fabricated with Cr, C and Ni mixed-powder by high energy milling and reactive carburising sintering. The elemental powders of Cr, C and Ni were mixed with proper ratio (Cr/C = 3:2 atomic ratio) and milled to the nanometre crystallite sizes (about 20–30 nm). Specimens were cold-isostatically pressed at 200 MPa and sintered at 1453, 1503 and 1553 K with vacuum atmosphere for 1 h, respectively. It was shown that the relative density of the sintered specimens increases first and then decreases slightly with increasing sintering temperature. The maximum values of the hardness (86.7HRA) and bending strength (1140 MPa) were achieved at 1503 K.