Analysis of singular interface stresses in dissimilar material joints for plasma facing components

Duplex joint structures are typical material combinations for the actively cooled plasma facing components of fusion devices. The structural integrity under the incident heat loads from the plasma is one of the most crucial i ssues in the technology of these components. The most critical domain in a duplex joint component is the free surface edge of the bond interface betwe en heterogeneous materials. This is due to the fact that the thermal stress usually shows a singular intensification in this region. If the plasma fac ing armour tile consists of a brittle material, the existence of the stress singularity can be a direct cause of failure. The present work introduces a comprehensive analytical tool to estimate the impact of the stress singul arity for duplex PFC design and quantifies the relative stress intensificat ion in various materials joints by use of a model formulated by Munz and Ya ng. Several candidate material combinations of plasma facing armour and met allic heat sink are analysed and the results are compared with each other. (C) 2001 Elsevier Science B.V. All rights reserved.