Joint formation mechanism of different laser transmission welding paths

Abstract

Abstract In this study, the rectilinear, sine, and spiral paths of polymer transmission welding were used to perform welding comparative experiments, and the influence of various parameters in the polymer transmission welding of different laser paths on the joint performance and the formation of molten pool was discussed. The spiral path exhibited the highest joint strength, that increased by more than 50% compared with conventional rectilinear welding. The molten pool formed by spiral welding had a high depth-to-width ratio. Microscope observations revealed that the glass fiber flow signs in the molten pool were obvious, the glass fiber in the molten pool was abundant, and the bubble generation rate in the molten pool was lower. In this paper, Fortran language was used to construct Gaussian body heat source movement model with different paths. Results show that the spiral welding had higher welding stability than traditional rectilinear welding, welding defects caused by the lack of heat in the previous period can be properly compensated by selecting the appropriate welding period, Therefore, good joint performance can be achieved. In addition, amplitude and period are two important process parameters of spiral welding, and their sizes have important effects on joint strength and molten pool formation