Microstructure and Properties of Fine-Grained WC-10Co-0.5Cr3C2-1TaC-0.5Ru Prepared by Rolling Ball Milling and Low-Pressure Sintering

Abstract

This study focuses on the preparation of fine-grained WC/Co composite powder using rolling ball milling and spray drying techniques. The cemented carbide composition achieved through low-pressure sintering technology was WC-10Co-0.5Cr3C2-1TaC-0.5Ru (wt.%). To study the effect of sintering temperature on the microstructure and mechanical properties of WC-10 wt.% cemented carbide, the microstructure and phase constituents of the material were analyzed using X-ray diffractometry and scanning electron microscopy. Additionally, the physical and mechanical properties of the material were examined. The results indicate that as the sintering temperature increased from 1390 °C to 1450 °C, the grain size of WC in the alloy increased, resulting in a slight decrease in hardness, an increase in fracture toughness, and the transverse fracture strength increasing first and then decreasing. The sintered hard alloy prepared at 1410 °C exhibited fewer pores and a uniform and fine grain size, reaching a density of 99.98%, a hardness of 91.8 HRA, a fracture strength of 3962 MPa, and a fracture toughness of 14.7 MPa⋅m1/2

Seeding ductile nanophase in ceramic grains

“…5(f), the average fracture strength of the present samples with in-grain nanophase is remarkably higher than those of the cemented carbides prepared using mixtures of WC and Co powders with an absence of in-grain nanophase in WC in the sintered bulk materials. 39,[44][45][46][47][48][49][50][51][52] Moreover, the enhancement of the fracture strength is achieved in the present samples without sacrificing their fracture toughness compared with those reported in the literature. 37 Therefore, it is believed that the formation of the ductile Co-rich nanophase and the modulated distribution of the nanophase within WC grains have significant positive effects on enhancing the combined mechanical properties of the cemented carbides.…”