(1. 西安交通大学 金属材料强度国家重点实验室， 西安 710049;
2. 西安交通大学 建筑工程与力学学院， 西安 710049)
摘 要: 应用扫描电子显微镜原位拉伸方法研究了纯铝/硬铝爆炸焊接界面微观断裂机制。结果表明： 在单向拉伸情况下， 在夹杂和应力集中等薄弱位置萌生的界面微裂纹为典型扩展金属/金属界面裂纹机制； 微裂纹以脆性方式导致界面分离，或以其裂尖区域位错发射的延性方式长大； 主裂纹和微裂纹以通过在界面一侧金属中其间韧带断裂方式连接， 最后失稳扩展。 在扩展路径上， 界面和金属交替出现， 且界面的断裂韧性不如相应单一材料的断裂韧性。
关键字: 爆炸层合板； 界面裂纹； 裂纹扩展； 原位拉伸
（ 1. State Key Laboratory for Mechanical Behavior of Materials,
Xi'an Jiaotong University, Xi'an 710049, China;
2. School of Civil Engineering and Mechanics,
Xi'an Jiaotong University, Xi'an 710049, China）
Abstract: The micro-fracture mechanism of explosive clad Al/LY12 interface were studied by scanning electronic microscopy (SEM) with in-situ tensile. The results indicate that, under uni-axial tensile, the microcracks mechanism of interface at the weak site of voids and debonding is interface cracks of metal/metal, and as well as the micro-cracks grow by means of brittle mode to debond interface or dislocation emission, blunting and sharpening. And each other of main cracks and microcracks coalesces through ductile or brittle fracture of the metal ligament. On the fractured interface, both the surfaces of the interface and metal exist alternately along the crack growth path. The fracture toughness of the bimetallic interfaces is lower than those of respective counterpart metals.
Key words: explosive clad metal; interfacial crack; crack growth； in-situ tensile
