TWI Industrial Member Report Summary 179/1982
By S B Dunkerton and W O Dinsdale
This report summarises the data previously presented on the Charpy impact properties of forge butt welds in a 0.2C-1.5Mn steel to BS 2772 150M19 together with limited data on continuous drive friction welds in two steels with low inclusion contents, a carbon steel to JIS G3103 Class SB49 and a carbon-manganese steel to BS 4360 Grade 50D. Where possible comparisons are made between the four forge welding processes examined, i.e. three variations on friction welding, continuous drive, inertia and orbital and flash welding.
It is shown that, with the exception of orbital friction welds, the as-welded Charpy impact properties of forge butt welds in 0.2C-1.5Mn steel to BS 2772 150M19 can be poor and are not significantly affected by changes in welding parameters. Orbital friction welds show an improvement in their as-welded toughness properties above O°C, which is believed to be a function of the orientation of the inclusions with respect to that of the Charpy specimens.
The work on the two 'clean' steels indicated that the as-welded impact properties of continuous drive friction welds can be good provided the carbon equivalent, carbon content and inclusion level ofthe parent steel are kept low.
Postweld heat treatment generally improved the Charpy impact properties of all the forge butt welds examined in the 0.2C-1.5Mn steel. but the levels of the heat treated parent material were not obtained.