抄録
New experimental technique for evaluating the thermal shock fracture characteristics of ceramic materials, Disc-on-Rod test, was developed. The specimen has disk shape with a diameter of 20mm and a thickness of 0.6mm, and the 2-dimensional thermal stress field was then obtained. The specimen was heated to high temperature and quenched by means of contacting with the cool metal rod with 4mm diameter. The temperature distribution of specimen was measured by a high speed IR camera and used for the determination of thermal stress field in specimen by FEM calculation. In order to evaluate the fracture process, AE signals during thermal shock fracture were detected. It was observed that the maincrack was initiated at the center region subjected to the maximum equi-biaxial stress. The critical stress for maincrack formation was evaluated and compared with that under mechanical loading, considering the volume effect of strength based on Weibull statistics.
