Compatibility of Zr2AlC MAX phase-based ceramics with oxygen-poor, static liquid lead–bismuth eutectic

Abstract

This work investigates the compatibility of Zr2AlC MAX phase-based ceramics with liquid LBE, and proposes a mechanism to explain the observed local Zr2AlC/LBE interaction. The ceramics were exposed to oxygen-poor (CO  2.210 -10 mass%), static liquid LBE at 500°C for 1000 h. A new Zr2(Al,Bi,Pb)C MAX phase solid solution formed in-situ in the LBE-affected Zr2AlC grains. Out-of-plane ordering was favorable in the new solid solution, whereby A-layers with high and low-Bi/Pb contents alternated in the crystal structure, in agreement with first-principles calculations. Bulk Zr2(Al,Bi,Pb)C was synthesized by reactive hot pressing to study the crystal structure of the solid solution by neutron diffraction.

Review of strategies toward the development of alloy two-dimensional (2D) transition metal dichalcogenides

“…Most of the attempts are synthesizing through powder metallurgy, which mainly depends upon either material self-lubricating properties or the addition of lubricating material for mechanical milling to avoid any foreign inclusion due to wear and tear ( Haji Amiri et al., 2020 ; Ma et al., 2020 ; Wang et al., 2020b ). There are also novel approaches recommended for formation, such as the arc-melting method, PVD and laser treatment, and molten salt route ( Bahiraei et al., 2020 ; Fattahi and Zarezadeh Mehrizi, 2020 ; Galvin et al., 2018 ; Tunca et al., 2020 ). Wang et al.…”

Processing of MAX phases: From synthesis to applications

“…Furthermore, different MAX phases were screened with respect to their interaction with oxygen-poor (C O ~ 5 × 10 -9 mass%), static and fast-flowing (v ~ 8 m/s) liquid lead-bismuth eutectic (LBE) for at least 1000 hours at 500°C. 87,88 No evidence of LBE dissolution attack was observed, despite the absence of a continuous external oxide scale. The local LBE interaction observed with the Zr-rich MAX phases consisted in the partial substitution of Al by Pb/Bi in the crystal structure and the in situ formation of (Zr,Ti) n+1 (Al,Pb,Bi)C n solid solutions.…”

“…Under these conditions, no alumina scale was formed leading to considerable corrosion of the materials except in the case of Cr 2 AlC, which was protected by a micrometer‐thin layer of Cr 7 C 3 . Furthermore, different MAX phases were screened with respect to their interaction with oxygen‐poor (C O ~ 5 × 10 ‐9 mass%), static and fast‐flowing (v ~ 8 m/s) liquid lead‐bismuth eutectic (LBE) for at least 1000 hours at 500°C 87,88 . No evidence of LBE dissolution attack was observed, despite the absence of a continuous external oxide scale.…”

Environmental degradation of structural materials in liquid lead- and lead-bismuth eutectic-cooled reactors

“…Fig. 5.10 shows SEM/EDS data on the local Zr 2 AlC/LBE interaction, which resulted in the in situ formation of a Zr 2 (Al,Pb,Bi)C MAX phase solid solution, due to the partial substitution of Al on the A-site by Pb and Bi [648]. Similarly, the static LBE exposure of the (Zr 0.8 ,Ti 0.2 ) n+1 AlC n MAX phase ceramic formed in situ a (Zr,Ti) n+1 (Al,Pb,Bi)C n solid solution due to the operation of a similar substitution mechanism [83].…”