A comparative study of the dry sliding wear of WC-10wt.%(Co+Fe+Ni) cemented carbides pressureless sintered with different Fe/Co ratios

Abstract

Compositional effects on the dry sliding wear resistance of micrometer-grained WC-10 wt.%(Co +Fe+Ni) cemented carbides pressureless sintered with 2 wt.% Ni but different Fe/Co ratios were investigated. Their microstructures are very similar except for the contiguity of the WC grains, which increased with increasing Fe/Co ratio. Also, these cemented carbides are all almost fully dense, but with the degree of residual porosity exhibiting a complex trend with increasing Fe/Co ratio (first decreasing and then increasing). The greatest densification was reached for an Fe/Co ratio of 1. The reverse trend was observed for the hardness, which reached HV 10 =1090 kg/mm 2 for Fe/Co = 1, indicative that it is dictated essentially by the porosity. The wear resistance correlated inversely with the porosity (and thus directly with the hardness), so that the densest (and thus the hardest) of these cemented carbides (the one sintered with a Fe/Co ratio of 1) also exhibited the lowest coefficients of friction, the lowest specific wear rates, and the lowest microstructural damage. The wear mode was abrasion, with the wear mechanism being plastic deformation and especially fracture. Thus, optimization of the wear resistance of WC-(Co+Fe+Ni) cemented carbides for tribological applications is feasible by a judicious design of their binder composition.

Mechanical and Tribological Characterization of WC-Co and WC-AISI 304 Composites by a Newly Developed Equipment

“…Comparison of results with previous investigations is not easy since there are no studies of evaluation of wear resistance to sliding wear with samples of WC-based composites with AISI 304 as a binder. However, it was possible to compare with some results by F. Djematene et al [ 35 ] that performed a comparative study of the dry sliding wear that uses WC-10 wt.% (Co + Fe + Ni), varying the percentage of Co and Fe in the binder (Ni was set to 2 wt.%). The wear performance correlated inversely with the porosity and thus directly with the hardness with the lowest specific wear rate to be observed for the specimen using a Fe/Co ratio of 1.…”

Microstructural and Mechanical Characterization of Colloidal Processed WC/(W5Vol%Ni) via Spark Plasma Sintering

“…Moreover, cobalt is not permitted for use in civil nuclear applications due to its capacity to absorb neutrons and become highly radioactive. Additionally, the temperature limit for cobalt usage is 800 °C [ 19 , 20 , 21 , 22 , 23 ]. Nickel has emerged as a promising alternative to cobalt, as it offers good wettability [ 24 ], lower toxicity, and better price compared to cobalt, along with improved corrosion resistance [ 25 ].…”