Surface Quality Detection of Laser Lap Welds and Its Influence on Joint Strength
H.Y. Xu, X.P. Gu, L.B. Wei, Y. P. Zhang, X. Q. Zhang and J. Dong
The non-contact laser ranging method was adopted to perform C-scan detection on the surface profile of SUS301L-DLT austenitic stainless steel lap laser welds produced with a fibre laser. The detected surface profile and metallographic analysis result shows that the non-contact detection result can reflect the surface state of laser lap weld joint, and through the slant correction and Gaussian fitting of the detected profiles, the complementary height and the surface width of the current section can be measured. Applying the section contour detection method to the C-scan detection, the average width and average complementary height of laser lap weld joint can be calculated. Comparative analysis shows that the tensile – shear strength of laser lap weld joint can be predicted by the average complementary height, which provides a methods for the non- destructive quality evaluation of laser lap weld joint.
Keywords: Fibre laser, SUS301L-DLT austenitic stainless steel, laser beam welding (LBW), lap weld, surface profile detection, laser ranging, C-scan detection, complementary height