Microwave sintering behavior of FeCuCo based metallic powder for diamond alloy tool bit

A novel method of microwave pressureless sintering to fabricate FeCuCo based diamond alloy tool bits was proposed. The characteristic of densification, mechanical properties and microstructural development of the microwave-sintered samples were investigated. Compared to the traditional sintering method in resistance furnace in this work, the microwave sintering displayed distinct advantages, including shorter sintering time, lower sintering temperature, more homogeneous element diffusion, more excellent holding force between in diamond and alloyed matrix. The result demonstrated that the designed metallic powders could be quickly heated to 850 °C in microwave field and heating rate for compacted mixed powder could even reach up to 30 °C/min. And also the relative density and hardness of samples were estimated to be 95.14% and 98.5 HRB by microwave sintering at 850 °C. Additionally, the microstructure analysis manifested microscopic texture was more uniform, which indicated that the microwave sintering was beneficial to the decrease of void defect in FeCuCo and diamond sintered compact. The possible microwave sintering mechanism was also discussed. This work will provide novel perspective of the sintering strategy for the metallic matrix superhard material tool field.