Influence of welding parameters on lap joint between Al and Ti alloys using low power fiber laser

摘要

Fiber laser beam welding has always been a user-friendly and flexible method to join dissimilar materials despite differences in thermal coefficient. Many industrial applications such as automotive has replaced the conventional joining methods towards this because of the flexibility and reduction in time consumption. In the present study, dissimilar titanium alloy; Ti6Al4 V and aluminum alloy; AA2024-0 were laser welded through a lap joint technique using a low power Yb-fiber laser without any additional filler. The influence of welding speed on weld morphology was investigated using optical microscopy (OM) and scanning electron microscope (SEM). The cross-section of the joints revealed that the fusion zone (FZ) and heat affected zones (HAZ) are wider when welding speed decreases with lower laser power. This result shows that the low power fiber laser has sufficient energy to melt the base materials, forming a liquid bridge to facilitate the smooth flow of molten metal between the top and bottom layer. Therefore, at lower welding speeds with constant low laser power, it was shown that there are possibilities of laser welding between two non-ferrous metals.