Study on the Evaluation of Mechanical Properties of Ceramic-Metal Joint

为了提高陶瓷-金属连接的可靠性，研究了合理的接头力学性能评价方法。1）作为一项基础性课题，验证了陶瓷-金属连接接头热应力的特殊性。为了找到减小热应力的方法，通过改变插入层的厚度和胶接接头的形状进行了分析。陶瓷-金属连接接头的实验结果表明，改变接头形状可以有效地降低热应力。2）获得了良好的陶瓷-金属连接接头，并对接头进行了三点弯曲试验。通过断口观察，即使在良好的接头中也发现了一些小的缺陷。3）通过数值模拟研究了陶瓷/金属弹性模量比E/E、嵌入层厚度、嵌入层弹性模量E等主要参数对J积分的影响。

In order to improve the reliability at the ceramics-metal joints, the rational evaluating method for the mechanical characteristic of the joints was studied. A summary of the obtained results in this study was as follows :1) As a fundamental subject, the special characteristics of the thermal stress produced in the ceramics-to-metal bonded joints were verified. In order to find a method of decreasing the thermal stress, analyses by changing the thickness of an insert layer and the shape of the bonded joint were carried out. The experimental results of ceramics to metal bonded joint showed that changing of the joint shape was effective in decreasing the thermal stress.2) The good ceramics-metal joints were produced and these joints were tested by using three points bending test. According to the observation of fracture surface, some small defects were found even in the good joints. It was shown that the evaluation of mechanical properties of bonded joints should e done by using the J integral.3) The effect of some dominant parameters (ceramic/metal Young's modulus ratio E/E , thickness of an insert layer, Young's modulus E of the insert layer) on the J integral of bonded joints was clarified by numerical simulation.