Patent ID: 9346124
Filing Date: 2016-05-24
CPC Classification: B21C,B23K,B41M

Claim Text:
1. A method for laser marking on a metallic member comprising: a base treating step of irradiating a base treatment target region including a marking target region on a marking target surface of said metallic member with a laser beam on a first irradiation condition; and a marking step of irradiating said marking target region with said laser beam on a second irradiation condition, thereby forming a marking pattern, wherein a charged energy of said laser beam on said first irradiation condition is set to be smaller than a charged energy of said laser beam on said second irradiation condition, thereby to provide between said marking pattern and a non-irradiation region which is not irradiated with said laser beam, a base region having a residual stress greater than that of said non-irradiation region and a residual stress smaller than that of said marking pattern.