Friction stir welding of steels - status report

TWI Industrial Member Report Summary 838/2005

By R Johnson

Background

Friction stir welding (FSW) is well established as a production manufacturing process with regard to fabrications in aluminium alloys, and is being used less widely for the welding of magnesium, copper and their alloys. The main obstacle to extending the FSW capability to the welding of steels is the selection of the FSW tool material to withstand the much higher temperatures of operation when plasticising steel in order to make a friction stir weld. This work investigates the current capabilities of the two leading contenders for an industrial FSW tool material.

Objectives

• To investigate the feasibility of friction stir welding steels using refractory metal friction stir welding tools.
• To generate comparative performance data using refractory metal and ceramic friction stir welding tools on ferritic steels.