Functionally Graded Tungsten-Copper Composites for Plasma Facing Components

Refractory metals such as tungsten are being considered for use as plasma facing components (PFCs) in fusion power reactors. Due to the enormous heat generated in the system, the refractory metal needs to be bonded to a heat sink, such as a copper alloy. Conventional materials processing leads to a sharp interface between the refractory metal and the heat sink. The thermal stress at the sharp interface negatively impacts the thermal shock resistance, the deformation characteristics, and the creep properties. Accordingly, this project will demonstrate the feasibility of generating a functionally graded interface, with a smooth transition between the plasma facing side of the heat shield (which is 100% tungsten) and the back side (which is 100% copper). Phase I will focus on demonstrating the enhanced mechanical properties of such a functionally graded material. In Phase II, prototype components will be fabricated and tested under typical use conditions. Commercial Applications and other Benefits as described by the awardeeSince fusion power is a potentially sustainable energy source, extensive global research and development work is underway to develop new materials in order to realize the benefits of fusion energy. The materials developed in this program are anticipated to be used as the first wall in a fusion reactor. Additional applications include cutting tools and specialty heat exchangers.