Abstract
Some ceramic-coated metals are nominated as first-wall materials. TiC-coated type-316 stainless steel is expected to be superior to other materials in high-temperature strength and in endurance properties under heavy irradiation. Delamination between the ceramics layer and base metal is considered to be one of the most important problems when such ceramic-coated metals are used in a gradient temperature field such as the first wall. In this report, the high-temperature strength of TiC-coated type-316 stainless steel, which is compared to the first wall of the fusion reactor, is investigated experimentally and computationally. A simple and precise thermal stress testing system is developed. The effects of surface roughness as well as the thermal stress and the residual stress on bond strength are investigated. Experimental and numerical results on residual stress distribution are compared mutually for confirming the reliability of the inelastic analysis of the finite-element method. It is expected that the suitable surface roughness decreases the residual stress in the coated film. The optimum range in the TiC-coating temperature is found by the inelastic FEM analysis for the heating condition used in the experiments.
