A low-temperature sintering preparation process of high-thermal-conductivity silicon carbide aluminum-based composite material

Abstract

This invention relates to the field of powder metallurgy preparation technology and discloses a low-temperature sintering preparation process for a high thermal conductivity silicon carbide aluminum-based composite material. The process includes: constructing a surface-embedded precursor; mechanically cold-welding irregularly shaped magnesium powder and spherical tin powder in an inert atmosphere and a low-energy ball mill shear field, and physically embedding them into the oxide film defects on the surface of the spherical aluminum powder to obtain modified aluminum powder with the magnesium-tin component anchored in a speckled pattern and the core maintaining a pure aluminum lattice; physically mixing the modified aluminum powder with silicon carbide powder and cold-pressing it; and performing in-situ activation sintering in a low-temperature range where solid-state atomic diffusion is limited, utilizing the anchored magnesium-tin component to generate a liquid phase in situ and reduce the oxide film to achieve densification. This invention, by constructing a mechanically embedded microscopic precursor, overcomes the limitations of atomic diffusion dynamics at low temperatures, achieving zero-distance contact and in-situ reaction between the additive and the oxide film.

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