Studies in Fracture and Materials Mechanics

该项目的目标是在以下三个方面促进现代工程材料力学的发展：(I)界面断裂力学，(Ii)薄膜和涂层中的失效模式，以及(Iii)非线性复合材料理论，重点是韧性材料的增强抗塑性流动和蠕变。人们正在尝试各种技术来改善不同材料之间的结合，将其应用于复合材料、分层电子封装和保护性涂层。建议研究塑性在提高界面和薄韧性粘结层混合模式韧性中的作用。将分析薄膜和涂层中的穿透裂纹和界面剥离是由小的裂纹状缺陷引起的。屈曲驱动的脱粘，这是薄膜和涂层在残余压缩下的主要失效模式，也将被研究。韧性材料的颗粒增强已成为开发高比刚度或耐高温蠕变新型结构材料的重要策略。我们工作的目的是提供一种机制来预测颗粒形状、体积分数和分布对增强材料整体塑性或蠕变行为的影响。

This project is aimed at contributing to the development of a mechanics of modern engineered material in the following three areas: (i) interfacial fracture mechanics, (ii) failure modes in thin films and coatings, and (iii) nonlinear composite theory with emphasis on reinforcement of ductile materials against plastic flow and creep. A wide variety of techniques are being tried to improve bonding between dissimilar materials with applications to composite materials, layered electronic packages, and protective coatings. Research is proposed to study the role of plasticity in increasing mixed mode toughness of interfaces and thin ductile adhesive layers. The initiation of through-cracks and interface debonding from small crack-like flaws in thin films and coatings bonded to substrates will be analyzed. Buckling-driven decohesion, which is the primary mode of failure for thin films and coatings under residual compression, will also be studied. Particulate reinforcement of ductile materials has emerged as an important strategy in the development of new structural materials with high specific stiffness or high temperature creep resistance. The goal of our work is to provide a mechanics for predicting the effect of particle shape, volume fraction and distribution on the overall plastic or creep behavior of the reinforced material.