TWI

The mechanical properties and microstructures of friction stir butt welds in 6.4 mm and 12.7 mm thickness quenched and tempered martensitic steel plate were compared with those of GMA butt welds in the same parent metal. The friction stir welds in the 6.4 mm plate were prepared using a polycrystalline cubic boron nitride tool with no preheating, no shielding gas and speeds of up to 3.28 mm/s. The same tool was used to weld the 12.7 mm plate, using argon shielding gas and speeds up to 1.9 mm/s. One run from each side was required. The welds were characterised by microstructural studies, and measurements of microhardness, tensile properties and Charpy V-notch toughness at -40 deg.C.

4th International Symposium, 14-16 May 2003, Session 10A: Steels 2, Paper 02