CuCrZr alloy hot cracking during electron beam welding

The precipitation hardened copper chromium zirconium material used in thermonuclear fusion machines has been selected for its good thermomechanical properties at high temperature, associated with the possibility of industrial assembling by electron beam welding. However, repeated occurrence of micro cracks which may propagate and then reduce lifetime, was observed. Consequently, the qualification of a crack-free electron beam welding technique for these copper alloys is a key issue and requires further investigation of the assembling process.