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在备有拉伸台的透射电镜上原位观察了ＳｉＣｗ／Ａｌ复合材料的变形、裂纹萌生及其扩展过程。结果发现，变形初期，位错主要从晶界及ＳｉＣｗ－Ａｌ界面处开动，在晶界与晶须周围产生大量位错。裂纹萌生源主要为：（１）材料制备过程中受损伤或破断的晶须；（２）晶须富集区。晶须与晶界对裂纹的扩展有阻碍作用。当裂纹取向与晶须大致垂直时，裂尖在晶须附近钝化然后绕过晶须扩展，当裂纹取向与晶须接近平行时，裂尖在晶须端部附近钝化后沿其一侧扩展。
The deformation, crack initiation and propagation of SiCw / Al composites were investigated in situ on a transmission electron microscope equipped with a tensile stage. It is found that dislocations mainly start from grain boundaries and SiCw-Al interfaces during the early stages of deformation, resulting in a large number of dislocations around grain boundaries and whiskers. The main sources of crack initiation are: (1) Damaged or broken whiskers during material preparation; (2) Whisker-rich areas. Whiskers and grain boundaries have an impediment to the propagation of cracks. When the crack orientation is approximately perpendicular to the whisker, the crack tip blunts around the whisker and then expands around the whisker. When the crack orientation is nearly parallel to the whisker, the crack tip is passivated along the whisker tip along one side Expand.