Laser marking of stainless steel with a Q-switched Nd:YAG laser

Laser marking of stainless steel with a Q-switched Nd:YAG laser has been studied in this paper. In experiments, three vital factors of a Q-switched Nd:YAG laser were chosen as control factors: electric current used for generating laser beam, pulse frequency and traverse speed of laser beam. Optical microscope and scanning electron microscope, surface profile instrument were used to measure effect of control factors on mark depth and width. An image-analysis system with a frame-grabber card and a charged-couple-device (CCD) was used to test mark contrast. The relationship between control factors and mark quality characteristics has been obtained.