半固态法制备混杂增强铝基复合材料的性能及增强机制研究

Study on Properties and Strengthening Mechanism ofHybrid Reinforced Aluminum Matrix CompositesPrepared by Semi-solid State Method

6061Al具有耐腐蚀、韧性好、易于成形加工、可焊性等优点,广泛用于建筑、运输、电子、航空、航天、兵器等各行各业,但因中等强度值限制了其更广泛的应用,大量研究表明采用外加增强体是有效方法之一。半固态加工技术避免了复合材料中增强体的飘浮、偏析等难题,为复合材料的制备和成形提供了有利条件。研究采用半固态加工技术,辅助机械搅拌制备SiC颗粒与Al 18 B 4O 33混杂增强6061Al复合材料,测试拉伸性能参数,分析界面结构与断口微观形貌,探讨混杂增强机理及裂纹萌生与扩展过程。

6061 aluminum is widely used in construction,transportation,electronics,aviation,aerospace,weapons and other industries,due to the outstanding corrosion resistance,remarkable toughness,easy forming,and good welding ability.However,moderate strength limits its other applications.Many researches prove that the addition of reinforcement phase is one of the effective methods.The semi-solid state method can solve the problem of reinforcement phase levitation and segregation in matrix,which provides favorable conditions for the preparation and forming of composite materials.In this paper,aluminum matrix composites hybrid reinforced with Al 18 B 4O 33 whiskers and SiC particles were prepared by semi-solid state method assisted with mechanical mixing.The tensile properties of composites hybrid reinforced were measured,and the interface structure and fracture micrographs were analyzed.The strengthening mechanisms were explored,and crack initiation and propagation were discussed.