TWI Industrial Member Report Summary 267/1985
By S B Dunkerton
Continuous drive friction welds have been produced in a range of ferritic steels in 25mm diameter bar form to determine the effect of steel composition on mechanical (bend and Charpy impact) and metallurgical properties. Both as-welded and postweld heat treated properties were related to the carbon content, alloying additions and inclusion content of the steels. The limits on compositional elements to satisfy bend properties are less stringent than those required for impact properties, but to satisfy both, carbon levels must not exceed 0.21%, the steel must be aluminium treated and not contain alloying additions of chromium, molybdenum or vanadium and, most important, the sulphur content should not exceed 0.02%. The properties obtained were also dependent upon welding conditions and the use of zero braking or high burn-off rates was necessary to yield acceptable as-welded impact properties.