PURPOSE: To effectively decrease and prevent the hydrogen embrittlement of an alloy member.
CONSTITUTION: The alloy member 5 subjected to an aging treatment over the entire part is prepd. The surface of the alloy member 5 is irradiated with a laser beam 8 and the surface of this irradiated part 9 is heated to a temp. above the solid soln. temp., by which the precipitate formed by the aging treatment in the alloy member 5 is solutionized and is dispersed into the structure. The irradiated part 9 is thereafter rapidly cooled at a solutionizing rate intrinsic to the material of the alloy member 5, by which the hydrogen embrittlement resistant part having the uniform structure without contg. the precipitate is formed on the surface of the irradiated part 9. As a result, the alloy member 5 having low hydrogen embrittlement sensitivity is obtd.
KATSUYA RYOICHI
YUKI MASAHIRO
MATSUI KENJI
