▎ 摘　　要

The mechanical properties of WC-6Co cemented carbides with different contents of graphene oxide (GO)/nanoalumina (Al2O3) composite particles were investigated. The results showed that some of the GO/Al2O3 composite particles were tightly wrapped in WC grains through boundary deformation, but some of them existed in the cobalt phase, which gradually decreased the cobalt phase lattice constant and caused different degrees of grain refinement. When the content was 0.05 wt%, the cobalt phase dissolved more W; thus, the solid solution strengthening effect was improved. In addition, the superior dispersion of the composite particles aided in particle refinement. The relative alloy density increased as the GO/Al2O3 composite particle content increased. The mechanical properties first increased and then decreased with increasing additive amounts. When the content was 0.05 wt%, the alloy had the best performance. The hardness was 2021 HV30, the strength was 2480.4 MPa, and the toughness was 11.5 MPa.m(1/2).