Abstract:Laser-weldable Si_p-SiC_p/Al hybrid composites with high volume fraction (60%-65%) of SiC reinforcement were fabricated by compression moulding and vacuum gas pressure infiltration technology. Microscopic observation displayed that the Si_p-SiC_p/Al hybrid composites with bilayer structure were compact without gas pores and the intergradation between Si_p/Al layer and SiC_p/Al layer was homogeneous and continuous. Further investigation revealed that the Si_p-SiC_p/Al hybrid composites possessed low density (2.96 g/cm³), high gas tightness (1.0 mPa×cm³)/s), excellent thermal management function as a result of high thermal conductivity (194 W/(m×K) and low coefficient of thermal expansion (7.0×10^-6 K^-1). Additionally, Si_p-SiC_p/Al hybrid composites had outstanding laser welding adaptability, which is significantly important for electronic packaging applications. The gas tightness of components after laser welding (48 mPa×cm³)/s) can well match the requirement of advanced electronic packaging. Several kinds of these precision components passed tests and were put into production.

Key words: Si_p-SiC_p/Al hybrid composites; laser welding; thermo-physical properties; electronic packaging