Enhanced Tooling for Friction Stir Technologies

Tool materials development has been the major limit for the application of friction stir technologies/welding (FSW) on hard alloys such as steels and titanium alloys over the past decade. During friction stir welding on steels, temperatures can exceed 1000°C, so the tool material needs to be strong enough to sustain wearing and deformation at elevated temperatures for long times. There are two major draw backs of tool materials developed previously: short life time and expensive processing routes. Therefore, it is urgent to develop a new low-cost tool material with longer life time. In this STTR program, QuesTek Innovations and University of North Texas (UNT) propose to design a WC-based tool material with refractory high entropy alloys (HEA) or MAX phases as binders, by combining Integrated Computational Materials Engineering (ICME) and experimental approaches. QuesTek will apply the ICME approach to design and optimize the WC-based tool material and UNT will process and test the material with their expertise in FSW. The final goal of this program is to design a suitable tool material for FSW on high strength low alloy (HSLA) steels and other alloys at a lower cost.