Ultra-sonic welding

The Navy experiments with ultra-sonic welding for Navy uniforms. The technique melts fabric together using sound waves. Ultra-sonic welding would make the uniforms lighter, stronger and cheaper. Welded seams are flexible and waterproof, too. Traditional seams create small holes that can trap air or water, which adds weight to Navy uniforms. The welding project could help bring manufacturing back to the U.S. from overseas.