FRICTIONAL PRESSURE WELDING METHOD AND ITS EQUIPMENT

PROBLEM TO BE SOLVED: To restrain the generation of a large quantity of reinforcement of weld generating in the joining stock having a low melting point at the time of joining as much as possible by first of all pre-heating the joining stock having a high melting point up to the vicinity of the melting point of the joining stock having a low melting point in the case of applying frictional pressure welding to joining stocks having different melting points. SOLUTION: The end surface 1a side of the joining stock having a high melting point is pre-heated up to the vicinity of the melting point of the joining stock 2 having a low melting point by high frequency induction heating, thereafter two joining stocks 1, 2 are mutually brought into contact to form the joining part 15, next one of joining stocks is rotated under a prescribed pressing force to generate frictional heat in the joining part 15, further the rotation is stopped at the time point when both joining stocks reach a softened state, and both joining stocks are frictionally pressure welded with an upset pressure applied. Also, chambers 11a, 11b having the feeding hole opening toward the inner part from the inert gas feeding path feeding an inert gas are provided around the joining part 15 of both joining stocks in the frictional pressure welding equipment. The high frequency induction heating device 10 heating one of joining stocks is provided in the chamber.