Interface connection mechanism and mechanical properties of WC_p titanium matrix composites fabricated by laser additive

Particle reinforced metal matrix composite structural parts have a wide range of prospects in aerospace, mechanical manufacturing, electronic and electrical fields. This study fabricated WC-reinforced TC4 matrix composites by laser selective melting technology. The effects of WC particle content and laser power on the microstructure and mechanical properties of the composite were investigated. The results show that: with the increase of WC particle content, the forming ability of composite samples decreases. When WC particle content is (0% ~ 15%), WC particles are evenly distributed, and no micro-pores and cracks are seen. When WC particle content is 20%, pores and cracks appear inside the material, making it difficult to form. At the interface of WC/matrix, an interface layer of TiC and W₂C is formed, and the interface bonding performance is good. With the increase of particle content and laser power in the composites, the fracture strength and elongation osf the composites decrease. The fracture mechanism is mainly the brittle fracture of WC particles and the lamellar tearing along the WC-W₂C interface.