Design and Manufacture of Pin Tools for Friction Stir Welding of Temperature-Resistant Materials

The primary goal of this SBIR Phase I project is to advance the development of low-cost, functionally graded laser additive manufactured high temperature refractory and cermet pin tools for friction stir welding (FSW) and/or friction stir processing (FSP) of heat-resistant materials. A solid state process, FSW produces high quality welds in difficult-to-weld materials and is fast becoming the process of choice for manufacturing lightweight transport structures including for space launch vehicles. Development of pin tools for FSW/FSP of the high temperature materials is a major challenge, as current pin tools are expensive and often fail prematurely. Production of pin tools using an Additive Manufacturing (AM) approach could offer a viable option for producing near-net shaped and relatively inexpensive functionally graded pin tools suitable for welding high temperature materials. The near-net-shape nature of this process not only minimizes the amount of machining and grinding involved, but also greatly reduces the time for manufacturing, or repair, of the pin tools.