Friction Stir Processing: A Potent Property Enhancement Tool Viable for Industry

Friction stir processing (FSP) has found commercial applications in several niche products (microelectronics, cutting blades, vacuum system hardware), but high-volume applications have yet to surface. Several industries have recognized the potential and are actively researching opportunities to use FSP to improve product performance and efficiency in automotive, aerospace, heavy vehicles, consumer electronics, power transmission, and applications in the defense sector. Only a small number of these have been reported in the open literature. Internal research groups within manufacturing companies explore new technologies, often in collaboration with Universities, National Labs or Contract Research entities, under nondisclosure environments to protect any early advantage that the new technology might provide in a competitive marketplace. As a result, it is often difficult to assess the technical readiness of a new technology until a product is revealed; at which point the technical readiness is quite high! Except for the niche commercial products, it is probably fair to put FSP at a Technology Readiness Level (TRL) of 4–5. Laboratory demonstrations of performance enhancement through FSP have been shown at full scale in relevant environments, but few have been demonstrated at the prototype part level integrated into subsystems (TRL6). To illustrate the readiness level, a few examples of some applications and current FSP research projects are described.