TWI Industrial Member Report Summary 815/2004
P L Threadgill and R Johnson
Background
Although friction stir welding is now established as a commercial process for joining aluminium alloys, considerable interest has been expressed in developing the process for alloys which must be welded at higher temperatures, for example titanium, steels and nickel. Steels in particular have been the focus of attention in recent years, and considerable progress has been made in developing the process for welding a number of different grades. Although development of the process for steels is far behind that of aluminium, it is becoming clear that exploiting the advantages of friction stir welding of steels is of considerable interest to a number of industrial sectors, although these are at present mainly in high added value fabrications. Factors such as low distortion, fully mechanised remote operation and low fume levels have all been cited as reasons for investigating the process in more depth.
This report represents a critical appraisal of the progress that has been made to date, highlighting both achievements and barriers to future progress which must be overcome.
Objective
The objective of this work is to review progress in friction stir welding of steels, and establish the current state-of-the-art.