Thermal stress intensity factor of interfacial cracks of a plasma facing component under high heat flux loading

One of the candidate design concepts for the plasma facing components for future Tokamak devices is a joint structure where armor tiles are bonded onto the heat sink substrate. For the fracture mechanical design of such a component, the loading characteristics of an interfacial crack should be described in terms of the thermal stress intensity factor (TSIF). Correlation between the TSIF and the thermal load for changing crack size is an important design issue. In this article, a fitting method is presented to determine the TSIF which includes the effect of temperature gradient and crack size requiring just small amount of numerical data sets. To this end, a modified formulation of TSIF is suggested. Test calculation was performed for an actively cooled beryllium-to-copper joint component. Results showed that present fitting scheme describes the effect of temperature gradient and crack size reasonably.