Fusion welding techniques, such as laser welding, electron beam welding, tungsten inert gas welding, plasma welding and others, commonly leave a pool of molten metal at the end of the weld pass that solidifies after heat input to the weld has terminated. The terminal pool is commonly the weakest portion of the weld and is often the site of fracture initiation under moderate to low stress. Welds produced in nickel-titanium alloys (nitinol) are particularly prone to this problem.
USPTO Backgrounds
USPTO Backgrounds