Patent ID: 7176401

Claim:
A welding method comprising: (a) an aluminum or aluminum alloy stud being brought into contact with an aluminum or aluminum alloy base material, the stud having a cylindrical shaft and a welding end with a substantially flat tip; (b) voltage being applied between the stud and the base material; (c) the stud being lifted slightly off the base material; (d) a pilot arc with a small amount of current being generated; (e) the main arc with a large amount of current being generated; (f) melting the tip of the stud and the section of the base material to be melted; (g) pressuring the molten tip of the stud against the molten base material in under five milliseconds after the main arc current has been cut off; (h) the end serving to centrally concentrate the main arc; and (i) welding together the stud and the base material.