Development of High Temperature Thermal Shock Fracture Toughness Measuring Apparatus and Its Application

材料在热应力或热冲击作用下的断裂力学性能作为热冲击断裂韧性等参数有必要进行综合评价；K_<IC>k/E α，其中K_<IC>为ⅰ型断裂韧性值，k为导热系数，E为杨氏模量，α为热膨胀系数。本课题研究的是热冲击断裂韧性测量装置的研制及其在实际应用中的应用。根据本研究的发展，通过热应力或热冲击来测量断裂力学性能已经成为可能，并且可以方便、合理地测量热冲击断裂韧性参数。该装置先后应用于高温气冷堆（HTGR）核心组分石墨和聚变反应堆装置（JT-60）面向等离子体第一壁组分C/C复合材料的测定。材料的热应力断裂广泛存在于摩擦学问题中，如旋转机器的机械密封和/或电机的碳刷。利用所研制的仪器对机械密封和电刷材料的关键性能参数进行了定量评价。

Fracture mechanics properties of materials subjected to thermal stress or thermal shock are necessary to evaluate synthetically as a fore of parameter such as the thermal shock fracture toughness ; K_<IC>k/Ealpha, where K_<IC> is mode I fracture toughness value, k is thermal conductivity, E is Young's modulus and alpha is thermal expansivity. This research study is the development of a measuring apparatus of the thermal shock fracture toughness and its applications to practical uses.According to this development study, fracture mechanics properties by thermal stress or thermal shock have become possible to measure easily and reasonably en block the thermal shock fracture toughness parameter up to 2000ﾟC.The developed apparatus was successively applied to the determinations of graphites as core components for a high temperature gas cooled reactor(HTGR) and C/C-composites as plasma facing first wall components for fusion reactor devices(JT-60).Thermal stress fractures of materials occur widely in tribology problems such as mechanical seals for rotating machines and/or carbon brushes for electric motors. The developed apparatus was used for the quantitative evaluations of their critical capable parameters of mechanical seal and brush materials.