Laser beam welding of materials like copper, lightweight aluminum alloys with high magnesium content as well as aluminum pressure die casting is still a challenge. Caused by facts like:
the high reflectivity,
low viscosity of the meld pool,
alloying elements with low evaporating temperature and
dissolved gases,
spatter, pores and melt pool ejection can occur with reduced process stability and will lead to bad weld seam quality. On the other hand for potential joining applications in the field of electro mobility and lightweight design stable laser welding processes are required.
The use of high power cw-laser source with brilliant beam quality and different wave length in combination with a high-frequent 2D beam oscillation is a promising approach to overcome these limitations. The influence of different wavelengths (515 nm and 1070 nm) for lasers with comparable beam parameter product and power up to 1000 W @ 515 nm and up to 5000 W @ 1070 nm were investigated. A keyhole modulation using a 2D high frequent beam oscillation up to 4 kHz was used for an improved weld process. As a result high quality welds with reduced porosity and less spatters occurred. The potential of this technology will be discussed for several materials and industrial applications for welding of aluminum pressure die casting of automotive components will be presented.
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