Overcoming oxidation and enhancing dispersion of nanoparticles via molten salt: Configurational distribution of TiCnp in pure Mg

Abstract

Nanoparticle-reinforced Mg matrix composites (NPMMCs) capitalize on the synergistic properties of nanoparticles and Mg matrix, resulting in enhanced mechanical attributes compared to matrix. Nonetheless, effective high-temperature dispersion of nanoparticles remains challenging. This study employs a molten salt dispersant (NaCl-KCl-MgCl₂) effectively mitigating the oxidation and combustion of TiC nanoparticles (TiC_np). Compared with the atmosphere, the molten salt facilitates the pre-dispersion of TiC_np through thermal motion at elevated temperatures, thereby reducing agglomeration between the TiC_np. Simultaneously, the molten salt effectively wets and disrupts the oxide layer on the surface of Mg melt, facilitating the wetting of TiC_np by the Mg melt. The successful incorporation of 3 vol.% TiC_np into the Mg matrix is achieved by utilizing molten salt, and the addition of TiC_np increases the viscosity of mg melt. Further dispersed by ultrasonic dispersion, the unique distribution of TiC_np within ring-like structures was obtained which was attributed to the increase of viscosity. As a configurational distribution, the ring-like TiC_np distribution morphology significantly enhances the mechanical properties of composites, as evidenced by an approximate 50 % increase in compressive strength (UCS).