Preparation of WC@graphene reinforced titanium diboride-based composite ceramic materials fabricated via SPS

Abstract

Liquid-phase laser irradiation technology was utilized to synthesize graphene-coated tungsten carbide (WC@G) core–shell composite materials with regular spherical morphology. Characterization via scanning electron microscopy, transmission electron microscopy (TEM), X-ray diffraction, and Raman spectroscopy revealed the evolution of WC particle microstructure from sharp edges to regular spherical shapes post-laser irradiation. High-resolution TEM displayed a tightly knit core–shell structure. Raman spectroscopy confirmed graphene presence through D, G, and 2D peaks. Incorporation of WC@G into a titanium diboride matrix, followed by discharge plasma sintering, yielded TiB₂/WC@G composite ceramic materials. Compared to TiB₂/WC/G composite ceramic materials, the WC@G core–shell structure significantly enhanced sintering performance. Optimal mechanical properties were achieved with 6 wt.% WC@G, exhibiting a relative density of 99.6%, Vickers hardness of 18.5 GPa, flexural strength of 696.9 MPa, and fracture toughness of 8.5 MPa m^1/2. Characterization identified graphene detachment, pull-out, and fracture deflection as key mechanisms enhancing toughness in TiB₂/WC@G composite ceramic materials.