Dynamic substrate reactions during room temperature heavy ion irradiation of CoCrCuFeNi high entropy alloy thin films

Abstract

High entropy alloys (HEAs) are promising materials for various applications including nuclear reactor environments. Thus, understanding their behavior under irradiation and exposure to different environments is important. Here, two sets of near-equiatomic CoCrCuFeNi thin films grown on either SiO2/Si or Si substrates were irradiated at room temperature with 11.5 MeV Au ions, providing similar behavior to exposure to inert versus corrosion environments. The film grown on SiO2 had relatively minimal change up to peak damage levels above 500 dpa, while the film grown on Si began intermixing at the substrate–film interface at peak doses of 0.1 dpa before transforming into a multi-silicide film at higher doses, all at room temperature with minimal thermal diffusion. The primary mechanism is radiation-enhanced diffusion via the inverse Kirkendall and solute drag effects. The results highlight how composition and environmental exposure affect the stability of HEAs under radiation and give insights into controlling these behaviors.

Aspects of Applied Chemistry Related to Future Goals of Safety and Efficiency in Materials Development for Nuclear Energy

“…The catastrophic accidents for traditional or other advanced reactors are minor affairs for the MMR—even when scenarios strike simultaneously [ 225 ]. Synergistic studies are needed to realistically evaluate the behavior of the alloys, where they are exposed both to the corrosive medium and to irradiation [ 226 ].…”

Ultrasonic imaging in highly heterogeneous backgrounds

“…• components where in the former case, the inclusions may be viscoelastic, anisotropic, and multiply connected, and (iii) a network of discontinuity surfaces Γ • ⊂ B characterized by the complex-valued and heterogeneous interfacial stiffness matrix K • (ξ) where ξ ∈ Γ • is the position vector. The specimen may be exposed to irradiation or chemical reactions as common producers of interfacial damage [31], and/or subject to thermal cycling, fatigue, and shock-waves which are mostly responsible for volumetric degradation [32] so that at any future sensing steps…”

“…In addition, the variational form (61) with (31) in light of the Rellich compact embedding theorem along with the regularity of the trace operator implies that…”

Phase Transformations Caused by Heat Treatment and High-Pressure Torsion in TiZrHfMoCrCo Alloy

“…HEAs are promising materials in many fields from medicine to the nuclear industry. Due to the fact that HEAs exhibit promising mechanical, magnetic properties and corrosion resistance, this combination of properties makes them potential candidates for components of next-generation nuclear reactors and other environments with high levels of radiation [ 6 , 7 , 8 ]. The second area of HEAs development is implants in medicine, as an analogue of replacing existing imperfect titanium ones.…”

“…The most commonly used approaches to the manufacture of HEAs are casting or arc melting technologies [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 ]. In this work, the HEA was obtained by levitation melting in an atmosphere of pure argon.…”