Sintering of nanophase WC-15vol. percent Co hard metals by rapid sintering process

摘要

A sintering method for the rapid sintering of a nanostructured hard metals in short time is introduced with a focus on the manufacturing potential of this novel high-frequency induction heated sintering (HFIHS) process. The advantage of this process allows very quick densification to near theoretical density and prohibition of grain growth in nanostructured materials. In this work, we developed a new process of sintering for nanostructured WC-15vol. percent Co hard metals. A highly dense WC-15vol. percent Co with a relative density of up to 99.4 percent was produced with simultaneous application of 60 MPa pressure and induced current within 1 min. The average grain size was about 258 nm and mean free path was about 11.6 nm. The fracture toughness and hardness values obtained were 11.9 Mparn~(1/2) and 1992 HV_(30), respectively. Also, we produced dense WC-Co hard metals with a relative density of 97 percent without applying pressure.