PURPOSE: To improve the nodular corrosion resistance of the zirconium alloy by irradiating the surface of a Zr-base alloy as a final manufactured article manufacture from a pure Zr sponge as raw material with corpuscular rays.

CONSTITUTION: Alloy elements are added to a pure Zr sponge 1 as raw material, which is subjected to arc melting, thereafter undergoes β-forging, solution treatment and α-forging, then is subjected to hot working and annealing, repeatedly to cold rolling and annealing and is thereafter irradiated with corpuscular rays to obtain the final manufactured article. As the irradiating corpuscular rays, electron rays and ions can be considered. As the temp. at which the corpuscular rays are emitted, the temp. range where the reformation of solid soln. of precipitated substance by the irradiation preferentially occurs and precipitation is hard to occur is needed to select. In this way, the depleted zone in the solid soln. components of the alloy elements produced in the Zr-base alloy at the manufacturing stage such as annealing and rolling can be eliminated. Thus, nodular corrosion caused by the above depleted zone can be suppressed.