StronSal® - laser soldering also trouble-free

The fewer the existing production methods and processes that have to be adapted, the faster new products can be used in automobile manufacturing. Ideally, there is little or no need to adjust parameters.
Laser soldering plays an important role when it comes to machining StronSal^®-coated body shell plates. This is the only joining technology that allows manufacturing to implement the designs that are common today. Therefore it was necessary to prove that laser soldering functions trouble-free with the StronSal® coating. The state of the art and benchmark is the appearance and quality of a soldered seam on electrolytically zinc-coated sheets.
Experts will see that naturally the general process conditions for laser soldering sheet steel with a StronSal^® coating are different than those for electrolytically zinc-coated sheets. The reason is the modified layer composition. The content of magnesium and aluminum influences the solder's melting and flow properties.
The examinations showed, however, that with the solder materials typically used in automobile manufacturing, StronSal^® can also be laser-soldered in the familiar way. The proof was carried out on samples that were similar to components and that emulate the joint forms in the area of a roof rail or a tailgate.
The soldering attempts at Salzgitter Mannesmann Forschung (SZMF) were not conducted on small laboratory samples. Instead, the idea was to uniformly and reliably produce an impressive 700-mm solder seam. Samples were compared directly to electrolytic zinc coating (ZE) and the StronSal^® coating (ZM).

In Figure 2, the top views onto laser-soldered seams that were produced both on an electrolytically zinc-coated sheet and on a StronSal® coating basis reveal that the solder's flow behavior was comparable in both cases and consequently also suggest that the quality would be comparable when painted.