Effects of laser scanning welding process on porosity rate of aluminum alloy

Research of 6061 aluminum alloy was done by using laser-scanning welding. The effects of such scanning parameters as track, width and frequency on porosity tendency were studied. The result showed that laser-scanning welding with the path of vertical, parallel and circular to welds can reduce the porosity of aluminum alloy compared with laser welding without scanning and the circular pattern was the best. The scanning width and scanning frequency of laser also have important influence on porosity, which can be controlled within 0.5% as the scanning width was greater than 0.65 mm and scanning frequency was from 100 to 220 Hz. The producing of porosity was associated with weld shape and the lower of depth-to-width ratio of the weld can help to control the porosity.