DEVELOPMENT OF EVALUATION EQUIPMENT FOR INTERFACIAL FUNCTIONS OF CERAMIC BASE COMPOSITES

陶瓷基复合材料的高温蠕变、断裂韧性等性能受到纤维或晶须与基体的界面结合的强烈影响，但目前还没有合适的直接测量界面结合的方法。本研究的目的是对复合材料施加应力，引起界面剪切或脱粘，然后测量内摩擦来评估界面脱粘的存在。准确地说，(1)：研制适用于高温条件下的扭摆内摩擦幅值依赖关系的刚性连接固定器；(2)：从幅值依赖关系评价复合材料的脱粘行为；(3)：将该技术应用于碳/碳复合材料；(4)：研究所研制设备的应用极限。我们成功地开发了一种适用于更高应力水平的内摩擦试验设备。得到以下结果：(1)：所研制的设备最大适用于1500 C和2.5 C， MgO的最大适用范围大于270 MPa；(2)：收集了已发表的C/C复合材料的数据；(3)：采用带弹簧和冲击罐的四元模型将内摩擦数据与高温蠕化数据进行了关联；(4)：对于MgO多晶材料，在800和1200个价位存在两个峰值，这两个峰值与扭转幅度超过晶体的墩应力密切相关。(5)：氮化硅陶瓷中界面玻璃相的黏度可以通过内摩擦数据来估算。

Properties as high temperature creep, fracture toughness etc. of ceramic base composite is strongly affected by the interfacial bonding between fiber or whisker and matrix, however, there is no suitable way of direct measurement of interfacial bonding. The purpose of this research is to apply a stress into the composite introducing an interfacial shearing or debonding and then measure the internal friction to evaluatc the existence of interfacial debonding. Precisely speaking, (1) : development of the rigid joining fixer for measuring the amplitude dependency of the internal friction by torsion pendulum applicable at high temperature, (2) : Evaluation of the debonding behavior of the composite from the amplitude dependency, (3) : application of this technique to the carbon/carbon composite, (4) : Investigation of the application limit of the developed equipment. We succeeded in to develop a excellent equipment of internal friction tester with higher level of stress applicable. Following results were obtained ; (1) : The developed equipment was applicable up to 1500ﾟC and 2.5ﾟ as a maximum amplitude, which was higher than 270 MPa for MgO, (2) : The published data of C/C composite were collected, (3) : The internal friction data was correlated to the high temperature crecp data by applying the four elements model with springs and dash pots, (4) : In case of MgO polycrystalline materials, there were two peaks at 800ﾟC and 1200ﾟC,which were strongly dependent on the amplitude of the torsion exceeding the piers stress of the crystal. (5) : The viscosity of the interfacial glassy phase in silicon nitride ceramics can be estimated by the internal friction data.