Additive Manufactured RF Load for ITER

High power RF loads are required to dissipate the power from gyrotrons used for heating fusion plasmas. The ITER facility, under construction in France, will require twenty four loads in its initial phase with an additional twenty four required for a future upgrade. High power RF loads are also required at other facilities under construction or planned. The current cost is very high due to the complex and rigorous performance specifications. Calabazas Creek Research Inc. (CCR) is applying additive manufacturing to dramatically reduce the cost of RF loads. CCR confirmed with the ITER office that material and performance specifications could be achieved using carbon fiber printed components. Test components were built (printed) and tested. The input coupler was redesigned to reduce reflected power, compatible with 3D printed components. The Phase I program determined that load cost could be reduced by approximately $90K while reducing weight by more than 400 pounds. The number of parts were reduced by more than half, and lead time for major components were reduced from months to days. Simulations indicate that the load will dissipate 1.5 MW CW of RF power with less than 0.25% reflected. These values significantly exceed ITER specifications. Additive manufactured (3D printed) component designs will be finalized, and conventional components optimized for cost and performance. A prototype, 1.5 MW CW RF load will be built and tested at high power. ITER will require a total of forty-eight RF loads. Loads will also be required for facilities under construction or planned in China, Korea, Japan, Europe, India, and the United States.