Comparative studies of WC-Co and WC-Co-Ni composites obtained by conventional powder metallurgy

Abstract

The present work reports a comparative study of cemented carbides of compositions WC-6Co, WC-10Co, WC-20Co, WC-6Co-6Ni and WC-12Ni-6Co. The purpose was to study the powder metallurgical production process of these compositions starting from a commercial WC-6Co powder, obtaining the desired compositions by mass balance with pure Co and pure Ni powders. During the process steps mixing, milling, compacting and sintering the powders were described by its apparent density, green density, shrinkage and sintered density. Lower densities were observed in composites with higher binder content. The process was monitored by scanning electron microscopy and EDS analysis to evaluate the homogeneity of the powders, to detect contaminations by the process and to characterize the microstructure of the sintered materials. A finer microstructure was found when the binder contained Ni. Potentiodynamic polarization tests in sulfuric acid revealed pseudo-passive behavior for all the tested hard metals.

The Analysis of Erosive Wear Resistance of WC-Co Carbides Obtained by Spark Plasma Sintering Method

“…The sintering technology involves the transformation of compressed powder into a solid material, which may be accompanied by shrinkage. Conventionally, pre-consolidated powders are sintered in resistance or induction heating furnaces, in a reducing or inert atmosphere [ 15 , 16 , 17 , 18 , 19 , 20 ].…”

Electroless Plating of Ni Nanoparticles on WC to Assist Its Pressureless Sintering of WC-Ni Cemented Carbide with Enhanced Mechanical and Corrosion-resistant Performance

“…Therefore, some literatures have appeared dealing with the preparation and characterization of Ni-bonded WC cemented carbides. Wentzel et al [5] and Martins et al [6] studied the influence of Ni content on the polarization behavior of WC-Co-Ni tungsten carbide. Chang et al [7,8] explored the optimal sintering process, sintering behavior and mechanical properties (bending strength, fracture toughness, hardness) of WC-15 (Fe, Ni) and WC-13.5 (Co, Ni, Fe) carbides and compared them with conventional WC-Co tungsten carbide.…”

Ferramentas de corte a base de carbonetos cimentados (metais duros) aplicadas ao torneamento de aço AISI 4340 endurecido: contribuição ao estudo de substituição ao sistema WC-Co por uma alternativa NbC-Ni.

“…A grande contração do metal-duro durante a sinterização é devida à excelente molhabilidade do WC no cobalto pela fase líquida, por volta de 1300 ºC (RODRIGUES et al, 2010, MARTINS et al, 2011e LABONNE 2020.…”