Sintering and irradiation of copper-based high entropy alloys for nuclear fusion

• Published in: Fusion engineering and design Vol. 146; pp. 1824 - 1828
• Main Authors: Dias, M., Antão, F., Catarino, N., Galatanu, A., Galatanu, M., Ferreira, P., Correia, J.B., da Silva, R.C, Gonçalves, A.P., Alves, E.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.09.2019; Elsevier Science Ltd
• Subjects: Ball milling; Beams (radiation); Body centered cubic lattice; Copper; Crystal structure; Entropy; Face centered cubic lattice; Fluence; Fusion reactors; Heat sinks; High entropy alloys; Irradiation; Irradiation damage; Microstructure; Nuclear fusion; Nuclear fusion reactors; Nuclear reactors; Plasma sintering; Spark plasma sintering; Thermal diffusivity; Tungsten; X-ray diffraction; High entropy alloys; X-ray diffraction; Microstructure; Irradiation damage
• ISSN: 0920-3796; 1873-7196
• DOI: 10.1016/j.fusengdes.2019.03.044

In this study, CuxCrFeTiV (x = 0.21, 0.44, 1 and 1.7 M ratio) high entropy alloys have been devised for thermal barriers between the plasma facing tungsten tiles and the copper-based heat sink in the first wall of nuclear fusion reactors. The high entropy alloys were produced by ball milling the elemental powders, followed by consolidation with spark plasma sintering. Irradiation of the equiatomic CuCrFeTiV sample was carried out at room temperature with Ar+ (300 keV) beams with a fluence of 3 × 1020 at/m2. Structural changes prior and after irradiation were investigated by scanning electron microscopy, coupled with energy dispersive X-ray spectroscopy, X-ray diffraction and thermal diffusivity. Preliminary results showed the presence of heterogenous and multiphasic microstructures in all samples. Moreover, with the increase of the Cu content it is possible to observe the formation of Cu-rich structures. The diffractogram of the CuCrFeTiV sample revealed major peaks of a BCC crystal structure and minor peaks of a FCC crystal structure. In addition, after irradiation no modifications in the CuCrFeTiV microstructure or in the diffractogram were observed.