A novel wear-resistant CoCrW-based alloy via heterogeneous deformation induced by carbides growth

摘要

A novel heterogeneous deformation CoCrW-based alloy with B4C addition is prepared via spark plasma sintering. Due to the decomposition of B4C[1-3] and the solid solution of C and B elements during sinte ring, the size of primary Cr 7C3 in the alloy grows, and the fracture mechanism changes from intergranular fracture to transgranular fracture, achieving high strength of 2535 MPa. Meanwhile, the large-size carbides absorb the frictional shear work by generating cracks, avoiding severe plastic deformation on the worn subsurface. At high temperature, the high strength alloy provides better support for the formation and stabilization of the glaze layer. As a result, the novel CoCrW -based alloy obtains excellent tribological properties with low wear rates of 1.31× 10 -5 and 6.5 × 10-6 mm3N-1m-1 at room temperature and 700 °C, respectively, accounting for only 49.6 and 33.7% of the of pure CoCrW alloy.