应用改进的虚裂纹闭合技术对热、力载荷作用下多材料构件连接区界面进行断裂分析。首先,通过对含橡胶夹层的复合材料层合板单腿弯曲(SLB)试件断裂分析,研究了在不同温度载荷作用下,橡胶夹层对试件能量释放率及其各型分量的影响。其次,对具有热流边界下,典型复合材料-橡胶-金属组成的多材料圆柱壳体连接裙结构进行了热力耦合断裂分析,结果表明裂纹总能量释放率随温度升高而增大。最后,针对该连接裙结构讨论了裂纹位置和橡胶层厚度对裂纹能量释放率的影响,指出适当增加橡胶层厚度可以降低裂纹能量释放率,但橡胶厚层度与界面韧性之间存在尺寸效应。
In this paper, a modified virtual crack closure technique proposed by author had been used to analyze the interface fracture of jointed area in multi-material components under a combined thermal and mechanical loading. Firstly, through the fracture analysis of a single leg bending (SLB) model which was established with a rubber sandwich under the different thermal loading, the rubber sandwich's influence on the energy release rate as well as each component was studied. Then, the interface fracture of typical multi-material cylindrical shell skirts composed by composite-rubber-metal under a combined thermal and mechanical loading, which had a heat flux boundary, was analyzed. It shows that the energy release rate of the interface crack gradually increases as the temperature rises. Lastly, the effect of the position of delamination and the thickness of the rubber on the energy release rate of each interface was discussed. It can be seen that there is a size effect between rubber thickness and interface toughness.