Nanocrystalline Cemented Carbides Sintered by the Pulse Plasma Method

Abstract

Nanocrystalline WC-12wt.%Co was consolidated by Pulse Plasma Sintering (PPS) at various temperatures between 900 and 1200oC for 6 minutes under a pressure of 60MPa. Cemented carbides sintered at 1100oC have a relative density of 99%, a hardness of 2248HV30, the fracture toughness, KIC=12.5 MPa*m1/2, and have a structure containing 50nm WC crystallites. Increasing the sintering temperature to 1200oC causes an increase in the size of the WC crystallite size to about 110 nm, reduces the hardness to 2198HV30, and decreases the KIC to 9.7 MPa*m1/2.