TWI

A review is presented of FSW (friction stir welding) tool design parameters and their relationship with heat generation, material flow and weld quality, including discussions of interaction mechanisms between tool and specimen, typical tool designs, emerging tool geometries and case studies. The fundamental principles of FSW are outlined with regard to heat generation by tool friction and material flow owing to tool stirring. The dependence of FSW joint quality on tool parameters such as shoulder diameter, pin size and shape is summarised. Case studies are reported for butt joint configurations using cylindrical and conical threaded pins, "Triflute" pins, "Whorl" pins and "Trivex" tools and lap joint configurations using "Flared-Triflute", "Skew" and whisk-type tools.

6th International Symposium, 10-13 Oct 2006, Session 1: FSW Tools, Paper 02