Thermal fatigue tests on disruption-damaged first-wall components

The possible synergistic effects between the thermal damage of a plasma disruption and the thermal fatigue lifetime of a bare first wall are investigated. The heat flux of a typical plasma disruption was applied on three stainless steel first-wall mock-ups by means of an electron beam gun. Then these damaged components were subjected to a thermal fatigue test to study the possible propagation of the cracks nucleated during resolidification. After 50 000 thermal fatigue cycles at relevant heat load conditions, no propagation was observed in spite of the high numerically computed stress level.