K. Kitamura et al., MECHANICAL-BEHAVIOR ON RESIDUAL-STRESS IN A TUNGSTEN-COPPER DUPLEX STRUCTURE AFTER CYCLIC HEAT LOADS FOR A DIVERTOR APPLICATION, Fusion engineering and design, 39-4, 1998, pp. 529-535
Cyclic thermal tests have been carried out on the tungsten-copper dupl
ex structures using an electron-beam test facility, with a particular
emphasis on the redistribution of the residual stress after the cyclic
heat loads of 14 MW/m(2)-2 s. The residual stresses on the tungsten s
urfaces were measured by the strain gauge method and compared with tho
se by thermoelasto-plastic analysis. Good agreement: was approximately
obtained for both their stress magnitude and distribution. Both radia
l and hoop stress components a, and a, on the tungsten top surface sli
ghtly increased after first heat cycle and then decreased with the inc
rease of the number of heat load cycles. Axial stress component a, on
the tungsten side surface also behaved in the same manner as stresses
on the top surface, while hoop stress component increased with the inc
rease of the number of heat cycles. Relaxation of residual stress was
induced with the elastic-plastic deformation of copper heat sink by cy
clic heat loads. (C) 1998 Elsevier Science S.A. All rights reserved.