Thermal and Irradiation Induced Stress Analysis on Relevant Target Plate Structure of the Divertor for Fusion Experimental Reactors

Abstract

This paper presents finite element analytical results of the thermal and irradiation induced stresses occurred in the target plate of the divertor structures which are exposed to neutron irradiation at 0-1 dpa with high heat flux up to 15MW/m². Three types of target plate models are studied in the present work, e.g., flat plate, saddle and mono-block type models which have bonded structures of one-dimensional high thermal conductivity Carbon-Carbon (C/C) composite material and Oxygen-Free-High Conductivity Copper (OFHC). With these results, it is concluded that flat model exhibits the longer life-time up to 1 dpa under 15 MW/m², whereas serious troubles, such as fracture in bonded interface or drop-off of armor tile from bonded substrate, are expected in saddle and mono-block type models before 1 dpa. Design change with reduction of the volume of armor region in the model is also effective to prolong the life-time by the reduction of sublimation of armor material.

KEYWORDS:

• fusion reactors
• divertor plate
• carbon-carbon composite
• copper alloys
• brazing
• flat plate
• mono-block type
• saddle type
• irradiation indused stress
• thermal stress
• thermal conductivities
• neutron beams
• irradiation
• radiation effects