Fabrication of W/Cu functionally graded materials used for nuclear fusion devices by VPS-EBW method and research of electron beam radiation

This paper introduces the fabrication method of W/Cu-FGM by Vacuum Plasma Spraying and Electron Beam Welding. Specimen could endure 20 s pluses under heat fluxes of 8 MW/m². No damages appeared in the tested specimens which endured 26 s, 22 s, 20 s pluses under 2.5 MW/m², 4.5 MW/m², 6 MW/m², respectively. Good performances were shown in the fatigue tests of the specimens. The specimens could endure 70 cycles fatigue under 6 MW/m² and 20 s pluses; No damages appeared after the specimens were subject to 100 cycles fatigue test under 2.5 MW/m², 30 s and 4.5 MW/m², 25 s. Crack began to come into being during 90 cycles fatigue at the heat fluxes of 6 MW/m², enduring 20 s. The specimen was analyzed by EDS. Impurities and pores were observed.