具有理想与非理想界面的双材料四点弯曲试件的界面断裂韧性

INTERFACIAL FRACTURE TOUGHNESS OF A BIMATERIAL FOUR POINT BENDING SPECIMEN WITH PERFECT OR IMPERFECT INTERFACE

本文作者用边界元法研究了具有理想与非理想界面的双材料四点弯曲试件的界面断裂韧性。分析了理想界面裂纹尖端的复应力强度因子以及非理想界面裂纹前沿的应变能密度与试件的几何尺寸、双材料的性质等的关系。计算结果表明，当裂纹的长度小于试件内支点的跨度时，上述两个物理量在很大范围内不随裂纹长度而变化。这种稳态的特性为两者的临界值的实验测定提供了方便。

Using boundary element method, a study is given on the interfacial fracture toughness of a bimaterial fourpoint bending specimen with either perfect or imperfect interface. The complex stress intensity factor and the strain energy density in the tip of interface cracks are calculated for these two kinds of specimens respectively. It is found that within most distance spanned by the inner loading points the above two quantities attain essentially constant values. This stable behavior will facilitate the test of interfacial fracture toughness.