CERN Accelerating science

Article
Title	Preparation Femtosecond Laser Prevention for the Cold-Worked Stress Corrosion Crackings on Reactor Grade Low Carbon Stainless Steel
Author(s)	John Minehara, Eisuke ; Nisimura, Akihiko
Affiliation	(JAERI/FEL, Ibaraki-ken JAERI, Ibaraki-ken)
Publication	2004
In:	26th International Free Electron Laser Conference and 11th FEL User Workshop 2004, Trieste, Italy, 29 Aug - 3 Sep 2004, pp.e-proc. THBOS02
Subject category	Accelerators and Storage Rings
Abstract	We report here that the femtosecond lasers like low average power Ti:Sapphire lasers, the JAERI high average power free-electron laser and others could peel off and remove two stress corrosion cracking (SCC) origins of the cold-worked and the cracking susceptible material, and residual tensile stress in hardened and stretched surface of low-carbon stainless steel cubic samples for nuclear reactor internals as a proof of principle experiment except for the third origin of corrosive environment. Because a 143 &deg;C and 43% MgCl<sub>2</sub> hot solution SCC test was performed for the samples to simulate the cold-worked SCC phenomena of the internals to show no crack at the laser-peered off strip on the cold-worked side and ten-thousands of cracks at the non-peeled off on the same side, it has been successfully demonstrated that the femtosecond lasers could clearly remove the two SCC origins and could resultantly prevent the cold-worked SCC.