Friction welding of aluminium alloy hollow members

摘要

The root shape of a flash formed in the friction-welded joint is controlled by introducing an upset delay time interposed between termination of the friction step and commencement of the upset step and by controlling the upset displacement speed. This provides a friction-welded joint having a tensile strength and a fatigue strength which are comparable with those of TIG- or MIG-welded joints and enables aluminum alloy hollow members to be produced by friction welding instead of TIG or MIG welding. Typically, the upset delay time is 0.4 to 0.8 sec and the upset displacement speed is 5.0 to 70.0 mm/sec to form a flash having a flash root radius of 0.5 mm or more and a flash root angle of 75 deg or less.