Surface tension stabilized laser welding (donut laser welding)-A new laser welding technique

A new laser welding process is presented which delivers a porosity free, spatter free weld. The process involves a donut shaped melt with a central hole of the same order of magnitude as the material thickness. The laser illuminates only the leading section of this melt. The hole is kept open by the melt surface tension. (C) 2013 Laser Institute of America.