Study on Generalized Criteria of Interfacial Strength between Dissimilar Materials

本课题的目的是建立粘结界面的广义断裂准则。通过对不同材料粘结界面损伤过程和断裂现象的观察，建立了基于损伤力学的界面损伤模型。然后，利用该界面损伤模型进行数值模拟，研究了界面断裂的广义断裂准则。进行了混合模态断裂试验，并对该广义断裂准则的有效性进行了研究。本课题的研究成果总结如下：1。提出了包括加载历史和界面摩擦效应在内的黏结区模型。进行了弹塑性和弹塑性混合断裂试验的数值模拟。则基于界面应力强度因子的断裂准则可描述为椭圆形状。结果表明，包含在界面应力强度因子中的特征长度…More可视为裂纹尖端前方的断裂过程区。利用该特征长度，在界面力学性能相同的情况下，可以得到任意一种材料对的广义断裂准则。进行了结合试件的混合模式断裂试验，得到了结合界面的断裂准则。结果表明，广义断裂准则可以应用于粘接断裂试验。提出了一种新的剥离试验方法来测量不同相位角下的界面强度。这种试验方法称为多级剥离试验。测定了Si/PI/Cr/Cu多层膜的剥离强度。在常规方法中，剥离膜的厚度影响剥离强度。而考虑稳态剥离时的能量平衡，可以得到与薄膜厚度无关的剥离强度。少

The purpose of this project is to establish the generalized fracture criteria for bonding interfaces. From the observation of damage process and fracture phenomena in bonding interface between dissimilar materials, interfacial damage model based on damage mechanics was developed. Then, by using this interfacial damage model to numerical simulations, the generalized fracture criteria of interfacial fracture were investigated. The mixed mode fracture tests were also conducted and the validity of this generalized fracture criteria was studied. The research results of this project are summarized as following,1. The cohesive zone model including loading histories and friction effect at the interface has been proposed.2. The numerical simulations for mixed fracture test under elastic and elastic-plastic analysis were carried out. Then, the fracture criteria based on the interfacial stress intensity factors can be describe as the elliptical shape.3. It is shown that the characteristic length … More included in interfacial stress intensity factors can be considered as the fracture process zone ahead of the crack tip. By using this characteristic length, the generalized fracture criteria can be obtained in any kind of material pairs if the mechanical properties of the interface are same.4. The mixed mode fracture tests for bonding specimen were conducted and the fracture criteria of the bonding interface were obtained. It is shown that the generalized fracture criteria can be applied to the bonding fracture test.5. The new peel test method to measure the interface strength under several kinds of phase angles has been developed. This test method is called as Multi-stages peel test. The peel strength of multi-layer films, that is composed of Si/PI/Cr/Cu, were measured. In conventional method, the thickness of peeled film was influenced to the peel strength. However, by considering the energy balance under the steady-state peeling, the peel strength independent of film thickness can be obtained. Less