Process Combines Arc, Laser Welding

A new hybrid laser welding technique could reduce processing time and costs associated with manufacturing tanks and pipelines for liquid gas.

The hybrid welding process forms a very narrow welding seam, seen here in an aluminum welding seam (cross-section above, top view below). Courtesy of Laser Zentrum Hanover.

Developed at Laser Zentrum Hannover eV (LZH), the approach teams a 16-kW solid-state disk laser with two gas metal arc welding torches. The laser and torch processes stabilize one another, the company said: The torches melt a layer of filler material, which absorbs energy from the laser and transfers it into the weld area between the two metal sheets.

The process can be used to make single-sided, zero-defect welds for aluminum sheets up to 12 mm thick at speeds up to 6 m per minute, the company said. Steel sheets up to 23 mm thick can be welded at 1.5 m per minute, which LZH said is 12 times faster than conventional processes. The system can bridge gaps up to 0.5 mm and edge misalignments up to 2 mm, the company said.

The new system’s seam geometry is very narrow and filler material consumption is considerably lower compared to arc welding processes. It also generates less heat, thereby reducing component distortion.

Development of the hybrid system was funded by the German Federal Ministry of Education and Research and supported by the Association of German Engineers.

For more information, visit www.lzh.de.