Manufacture of gradient WC-co composite and its mechanical property evaluation

In this study, two different compositions of WC-Co composite with gradient microstructure are designed and manufactured with the average cobalt content of 10 wt% and 8 wt% individually. Microstructure analysis and EDS test results confirmed the existence of a gradient distribution of cobalt content in the manufactured WC-Co composite. Mechanical properties including abrasive wear resistance, fracture toughness, bending strength, static compressive resistance, compressive fatigue resistance, and impact resistance were all conducted on both designed gradient WC-Co composite and homogenous WC-Co composite with the similar cobalt content and hardness. The mechanical test results demonstrated that the manufactured gradient WC-Co composite exhibited significant advantages in abrasive wear resistance, static compression resistance, compressive fatigue resistance, and impact toughness compared with homogenous WC-Co composite, while showing comparable performance in fracture toughness and bending strength. The relationships between the mechanical properties and microstructure of gradient WC-Co composite were studied for further potential performance improvement.