摘要
Laser-weldable Sip-SiCp/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 Sip-SiCp/Al hybrid composites with bilayer structure were compact without gas pores and the intergradation between Sip/Al layer and SiCp/Al layer was homogeneous and continuous. Further investigation revealed that the Sip-SiCp/Al hybrid composites possessed low density （2.96 g/cm^3）, high gas tightness （1.0 mPa·cm^3）/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, Sip-SiCp/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·cm^3）/s） can well match the requirement of advanced electronic packaging. Several kinds of these precision components passed tests and were put into production.
结合预制件一次性模压成型和真空气压浸渗技术制备具有双层结构的高体积分数（60%~65%）、可激光焊接 Sip-SiCp/Al 混杂复合材料。该复合材料的组织结构均匀、致密，增强相颗粒均匀地分布在复合材料中， Sip/Al-SiCp/Al界面均匀、连续、结合紧密。性能测试表明，Sip-SiCp/Al 混杂复合材料具有密度低（2.96 g/cm^3）、热导率高（194 W/（m·K））、热膨胀系数小（7.0×10^-6K-1）、气密性好（1.0×10^-3（Pa·cm^3）/s）等优异特性。焊接试验表明， Sip-SiCp/Al 混杂复合材料具有良好的激光焊接特性，其焊缝平整、致密，微观组织均匀，没有生成明显的气孔和脆性相Al4C3。同时，Sip-SiCp/Al混杂复合材料激光封焊后优异的气密性（4.8×10^-2（Pa·cm^3）/s）能够满足现代电子封装行业对气密性的严格要求。
