Internal distribution of residual stresses in fiber laser welded materials using a minute metal powder

Shobu, Takahisa  ; Okazawa, Kazuhiro; Muramatsu, Toshiharu; Takase, Kazuyuki; Tsukimori, Kazuyuki; Minehara, Eisuke*

At the commercial use stage in sodium-cooled fast breeder reactors, a securing maintenance and repair more than the equal to that of present water-cooled reactors is requested. We are aiming at the standardization of fiber laser welding technology using minuteness metal powder that three-dimensional micro-fabrication is possible as the repair technology. In the present study, the internal distribution of residual stresses in materials by the welding technology is evaluated methodologically. Now, the specimens welded under various laser conditions were made for the S50C (steel with 0.50% carbon). The surface residual stress of the specimens is measured by using laboratory X-rays. On the other hand, the measurement of internal distribution of residual stress will be carried out by using high energy synchrotron radiation X-rays in the SPring-8 facility.