Effect of Mo2C additions on the properties of SPS manufactured WC–TiC–Ni cemented carbides

• Published in: International journal of refractory metals & hard materials 2013-11, Vol.41, p.12-21
• Main Authors: Genga, R.M., Cornish, L.A., Akdogan, G.
• Format: Article
• Language: English
• Subjects: Densification; Mechanical properties; Molybdenum carbide; Nickel; Spark plasma sintering; Wettability
• ISSN: 0263-4368; 2213-3917
• DOI: 10.1016/j.ijrmhm.2013.01.008

The effect of spark plasma sintering (SPS) on the microstructure and mechanical properties of WC–Co and WC–Ni cemented carbides was studied, and compared to WC–Co produced by liquid phase sintering (LPS). There were finer WC grains with larger Co pools in the spark plasma sintered WC–Co, resulting in higher hardness and slightly lower fracture toughness than the liquid phase sintered WC–Co. The influence of the addition of 0.5–5wt.%Mo2C to WC-based cemented carbide containing 6.25wt.%TiC and 9.3wt.%Ni prepared by SPS was also studied. This addition improved the wettability between WC and Ni and lead to the improvements of microstructures, resulting in good combinations of hardness, fracture toughness and modulus of elasticity that were comparable to WC–Co based cemented carbides. ► The SPS WC–Co alloy had finer WC grains but larger (Co) pools than the LPS sample. ► WC–Co alloys had slightly higher moduli of elasticity than WC–Ni alloys. ► Mo2C addition necessitated higher sintering temperatures to achieve good density. ► Addition of Mo2C resulted smaller and more evenly distributed (Ni) binder pools. ► Mo2C improved hardness and elastic modulus, without changing fracture toughness.