Effect of Auxiliary Gas and Light-Absorbing Coatings on Laser Surface Texturing

Abstract

This research article seeks to improve the quality of micro-dimples and laser processing efficiency. The effect of auxiliary gas types and light-absorbing coatings on the dimple quality were experimentally investigated on the surface of H13 die steel. W-71s spray gun was used to coat the surfaces of H13 die steel material with different coating materials. The micro texturing process was done by Nd:YAG laser machine and the morphology of the micro dimple was measured and analyzed by a three-dimensional profile analyzer. The results showed that when nitrogen is used as auxiliary gas, the dimples are of better quality and the surface hardness of the textured area is also significantly improved. However, the processing cost is very high as compared to air and oxygen gas. Compared with the uncoated specimen, the single-coated water glass and yellow metal primer greatly improve the quality of the micro dimples and the laser processing efficiency. The dimple volume for the single-coated yellow metal primer specimen increased by 30.5% as compared with the uncoated specimen, whiles the slag volume for the single-coated water glass specimen has been reduced by 45.2%. Compared to the single coatings, the composite coating of water glass and yellow metal primer have better laser processing efficiency. Compared to uncoated specimens, dimple volume and slag volume for the composite coating of water glass and yellow metal primer increased by 41.9% and 11.7% respectively. This result is very instructive for improving the machining efficiency and the surface quality of laser surface textures.