METHOD OF LASER WELDING OF METALS Russian patent published in 2006 - IPC B23K26/20 

FIELD: mechanical engineering; impulse laser welding.

SUBSTANCE: invention can be used for spot and seam welding of ferrous and nonferrous metals of high oxidative activity without filler material. Welding is done by complex shape laser pulse. Under action of sharp leading edge of pulse, high-melting oxide film is heated to its evaporation point. Laser reaches its peak in power density value during time . Complete evaporation of oxide film from surface of metal to be welded takes plate within . Trailing edge of pulse has several smoothly falling down and flat sections. Metal is heated to melting point on section . Part of energy is taken for reflection. Metal is melted and melted through in thickness at power density during . Further reduction of power density leads to cooling, reduction of temperature below melting point and crystallization of welded metal. Stepless reduction of power density during and its maintaining at density during provides thermal treatment process ensuring reduction of defects to tolerable level or complete elimination of defects.

EFFECT: improved quality and increased capacity of welding.

7 ex, 5 dwg