DEVELOPMENT OF EVALUATION EQUIPMENT FOR INTERFACIAL FUNCTIONS OF CERAMIC BASE COMPOSITES

陶瓷基复合材料的高温蠕变、断裂韧性等性能受纤维或晶须与基体界面结合的影响很大，但目前还没有合适的方法直接测量界面结合。本研究的目的是在复合材料中施加应力，引入界面剪切或脱粘，然后测量内摩擦来评估界面脱粘的存在。具体而言，（1）开发了用于高温下利用扭摆法测定内耗振幅依赖性的刚性连接固定器，（2）根据振幅依赖性评价了复合材料的剥离行为，（3）将该技术应用于碳/碳复合材料，（4）研究了开发设备的应用极限。研制成功了一台性能优良、适用应力水平较高的内摩擦力测试仪。获得了以下结果：（1）：所开发的设备适用于高达1500 ℃和2.5 ℃作为最大振幅，这高于MgO的270 MPa;（2）：收集了已发表的C/C复合材料的数据;（3）：通过应用具有弹簧和缓冲器的四元件模型，将内摩擦数据与高温crecp数据关联，（4）：在MgO多晶材料的情况下，在800 ° C和1200 ° C处有两个峰，这强烈依赖于超过晶体的墩应力的扭转幅度。(5)氮化硅陶瓷中界面玻璃相的粘度可以通过内耗数据来估算。

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.