Plasma and Fusion Research

Volume 17, 1405049 (2022)

Regular Articles

Direct Tungsten/Copper Bonding for Divertor Application
Keisuke YAMAUCHI, Naoki SANO and Katsuaki TANABE
Department of Chemical Engineering, Kyoto University, Nishikyo, Kyoto 615-8510, Japan
(Received 21 February 2022 / Accepted 30 March 2022 / Published 22 April 2022)


We carried out a fundamental investigation of a uniaxial direct W-to-Cu bonding at relatively low temperatures in ambient air, which would potentially allow for simple preparation and maintenance of divertor wall components. W/Cu bonds formed at 500°C with a bonding pressure of 0.1 MPa, but the mechanical interfacial strength was about 1 MPa, significantly lower than the state-of-the-art values for bonding around at 1000°C in vacuum. Higher degree of interfacial oxidation and atomic interdiffusion were observed for higher bonding temperature, through x-ray photoelectron spectroscopy. The electrical conductivity across the bonded W/Cu interface, an indicator of thermal conductance, was measured to be lower for higher bonding temperature, presumably due to the interfacial oxidation.


nuclear fusion reactor, plasma-facing wall, divertor, armor, heatsink, bonding, brazing, tungsten, copper

DOI: 10.1585/pfr.17.1405049


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