Cermet materials reinforced with a small addition of spinel nanoparticles for molten salt power systems. Issue 1 (May 2021)

• Record Type: Journal Article
• Authors: Agureev, L E; Ivanov, B S; Laptev, I N; Ivanov, A V; Ashmarin, A A
• Is Part Of: Journal of physics. Volume 1925:Issue 1(2021)
• Publication Date: 2021-05
• Subjects: Physics -- Congresses; 530.5
• DOI: 10.1088/1742-6596/1925/1/012002
• Languages: English
• ISSNs: 1742-6588

Abstract

Abstract: This work is devoted to developing of new cermets for molten-salt power systems, promising for use in aviation, rocket and space technology, and power engineering. The production of cermets in the nickel-aluminum alloy system - 35 wt. % aluminum oxide by the method of mechanical activation and spark plasma sintering was carried out. It was found that the addition of 5 wt. % yttrium oxide, as well as small quantities (0.1 wt. %) of aluminum-magnesium spinel nanoparticles, increase the strength of the cermet at elevated temperatures. Cermets have high strength at room and elevated temperatures, which amounted to 480-530 MPa at 20 °C and 430-470 MPa at 750 °C. The micro structure of cermets was characterized by the presence of elliptical regions, the grains in which were significantly smaller than the grains in the surrounding matrix. This structure allows to effectively harden the material because elliptical areas are obstacles to crack propagation. Elliptical zones have length ranged 100 to 200 μm and width 5 to 20 μm. It was found that the material of the NiAl-Al2 O3 system at 20 °C and 800 °C contains the phases NiAl, Al2 O3, and Ni2 Al3 . Composite composition NiAl-Al2 O3 -Y2 O3 at 20 °C and 800 °C retains the three-phase composition of NiAl, Al2 O3, and Y2 O3 . Both materials are stable up to 800 °C.