Joining Plasma Resistant Lanthana Doped W and CuCrZr Alloy Heat Sinks for Use in Nuclear Fusion Applications

In the ITER, an international fusion experiment, a magnetically confined cloud of super hot plasma maintains the fusion of tritium and dueterium. The water-cooled diverter cartridge, which removes the charged species generated by the fusion reaction, experiences a harsh environment of rapidly fluctuating temperature. In this environment, the joint between the tungsten plasma facing material on the diverter and the water-cooled CuCrZr alloy heat sink is subject to thermal fatigue cracking. The reliability of these joints is critical to the success of the ITER project, because (1) an efficient fusion process requires the reactor to operate continuously over large periods of time, and (2) inspection of the diverter components would require weeks of down time. This project will develop technology for thermal-fatigue-resistant joints. Phase I will take advantage of recent advancements in powder metallurgy technology to create structurally optimized joints using copper tungsten nano-powders. Commercial Applications and other Benefits as described by the awardee The manufacturing techniques explored in this program would be applicable to many similar high energy situations, such as in super-critical steam-based power generation, vehicle armor systems, and next generation brake pads.