METHOD OF MAKING HEMMED JOINTS UTILIZING LASER WELDING

摘要

METHOD OF MAKING HEMMED JOINTS UTILIZING LASER WELDING Methods of laser welding zinc coated galvanized steel are disclosed. In a method that relates to forming hem joints for motor vehicle body components a sheet of steel is provided with a plurality of V-shaped tabs. When a hem joint is formed the V-shaped tabs together with a surface of another sheet of steel form gas venting channels that provide an escape passage for gas vapors that are developed when the zinc coating is vaporized by laser welding. In another method of laser welding, one of the steel sheets has an axially extending wall that is V-shaped to provide a V-shaped groove and the wall has spaced gas vent holes.