Investigations of the mechanical properties and structure of laser welds for ITER divertor and first wall

The weld material has been found to have a higher yield strength than the base metal, i.e. Rp0.2 = 344 MPa at RT. It is shown that the laser weld material is capable of withstanding without cracking the uniform elongation up to 45% and true stresses up to 850 MPa. The weld structure and the microhardness distribution in the base metal and in the weld have been investigated. Fracture of the laser weld material is of ductile transcrystalline character. The conclusion has been substantiated, that the proposed testing methodology provides engineers and designers of ITER high-heat flux components with more complete information on the properties of laser welds than the standard method.