Abstract
On the basis of our analysis of a transient thermal stress problem of a thin circular disk, which is locally heated at an arbitrary eccentric position, influences on thermal stresses and stress intensity factors in the thermal shock testing condition of the disk specimens are discussed. Then, measuring methods of the thermal shock resistance and the thermal shock fracture toughness by arc discharge heating are explained. These methods are applied to several kinds of graphite and C/C-composite as the first wall materials in fusion reactor devices. The results are compared with preliminary observations of the plasma-facing first wall tiles for a fusion reactor device JT-60. (Author)