Initial Investigation of the Orbital Friction Welding of Mild Steel

TWI Industrial Member Report Summary 270/1985

By A K Cousens and M J Camping

Background

In the friction welding process, heat is generated by pressing two surfaces together and forcing one to move with respect to the other. There are a variety of mechanical methods of achieving relative motion between the two components to be joined. One method, which has received little attention to date, is to cause one of the components to orbit around a fixed point on the other surface. Several significant advantages are claimed for this mode of friction welding. This report presents the results of a study which compared welds in both solid and tubular parts made by the orbital method with welds made by conventional rotary friction welding. Welding process parameters were investigated, and the welds produced were mechanically tested (in bend and tensile tests) and metallographically examined. It is concluded that important differences exist between the two welding processes. It is shown that satisfactory welds can be produced in mild steel by the orbital process, with a saving in time and a reduction in friction pressures necessary to produce similar welds by the conventional rotary welding method.