TWI

Using a pin tool made from relatively low cost metallic materials, including heat resistant alloys (e.g. Ni-Cr) with or without surface treatment, suitable conditions were investigated for friction stir welding (FSW) of commercially pure (CP) titanium and Ti, 6%Al, 4%V alloy (both 3 mm thickness). Stir on plate tests (800 rpm rotational speed, 1.67-3.33 mm/s welding speed, 19.9 kN load) were performed to determine appropriate FSW conditions. Tool tips were surface treated by nitrogen or fluorine ion implantation. In an attempt to prevent oxidation, argon gas was sprayed on the pin tool and specimens during welding. Results are presented for tensile strength, Vickers hardness distribution, appearance and microstructure of weld cross sections for the CP titanium.

6th International Symposium, 10-13 Oct 2006, Session 13B: FSW of Ti Alloys, Paper 02