Patent ID: 7419082
Filing Date: 2008-09-02
Classification: B23K

Abstract:
1. A friction welding process comprising the steps of providing a first workpiece comprising a first weld zone having a first weld surface and a second workpiece comprising a second weld zone having a second weld surface, at which weld zones the workpieces can be welded together, arranging the workpieces in engagement with each other at said weld surfaces, effecting oscillatory motion of the workpieces relative to each other such that at least one weld surface moves across the other, thereby raising the temperature at said weld surfaces to create a weld interface, and ceasing said relative oscillatory motion and allowing the weld surfaces to cool to weld the first and second workpieces together at said interface, wherein the first weld zone has an outwardly extending portion and the first weld surface is provided on the outwardly extending portion, the outwardly extending portion has a generally triangular profile formed by two side faces which taper relative to an apex region which engages the second weld surface, the width of the apex region being less than the maximum amplitude of the oscillatory motion and the angle of the tapered surfaces being sufficient to provide a gap between the side face and the second weld surface, continuing oscilation of said workpieces in order to form the aforementioned gap with a sufficient size to allow weld flash material formed during said oscillatory motion to pass from the weld interface through said gap to expel weld anomalies and defects from the weld interface.