Repair welding of etched tubular components of nuclear power plant by Nd:YAG laser

In this paper the possibility to repair etched tubular components of nuclear power plant by Nd:YAG laser is investigated. Experimental results indicate that the residual stresses of welds increase the sensitivity of stress corrosion cracking. A structure with low restraint and equipment to realize the welding on the inner wall of sleeve are designed. The high energy density of Nd:YAG laser produces deep penetration and can weld sleeve with tube. The microstructures and mechanical properties of welded joint are studied. The base metals of sleeve and tube are not severely affected by the heat of welding. The weld metal is ductile and its tensile shear strength is about 60% of that of Inconel 600 tube. Experiments indicate that it is a suitable method to repair etched tubular components of heat exchanger by Nd:YAG laser.