Abstract

High-entropy alloys (HEAs) consisting of five or more components in an equimolar ratio are attracting increasing attention due to a unique combination of various properties. Doping HEAs with small amounts of certain elements (most often rare earth, trace or noble metals) is a promising way to improve the characteristics of such alloys and to control their properties. This paper reports the results on the microstructure, phase composition, and microhardness of as-cast Ag_xAl_0.5CoCrCu_yFeNi HEAs (x = 0, 0.1; y = 0.5, 1.0). The effect of silver addition on the oxidation behavior of the studied HEAs at 700°C was determined. The morphology, phase and chemical composition of the resulting oxide film were studied. It was shown that the introduction of silver improves the mechanical characteristics of the alloys, but deteriorates the oxidation resistance due to the formation of copper-silver eutectic in the alloy microstructure, leading to a change in the morphology and phase composition of the formed oxide layer. Along with the solid solution of (Al, Cr)₂O₃ oxides and CuCr₂O₄, NiCr₂O₄ spinels, the addition of silver leads to the formation of copper oxide CuO and a small amount of silver oxide Ag₂O in the surface film.

中文翻译：

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添加银对Al0.5CoCrCu0.5FeNi和Al0.5CoCrCuFeNi高熵合金显微组织、相组成、显微硬度和表面氧化层形成的影响

摘要

由五种或更多等摩尔比成分组成的高熵合金（HEA）由于各种性能的独特组合而受到越来越多的关注。用少量某些元素（最常见的是稀土、痕量或贵金属）掺杂 HEA 是改善此类合金特性并控制其性能的一种有前途的方法。本文报道了铸态 Ag _x Al _0.5 CoCrCu _y FeNi HEA ( x = 0, 0.1; y = 0.5, 1.0) 的显微组织、相组成和显微硬度的结果。确定了银添加对所研究的 HEA 在 700°C 下氧化行为的影响。研究了所得氧化膜的形貌、物相和化学成分。结果表明，银的引入改善了合金的机械性能，但由于合金显微组织中铜银共晶的形成，导致所形成的氧化层的形貌和相组成发生变化，从而降低了合金的抗氧化性。 。随着(Al,Cr) ₂ O ₃氧化物和CuCr ₂ O ₄、NiCr ₂ O ₄尖晶石的固溶，银的加入导致形成氧化铜CuO和少量氧化银Ag ₂ O。表面薄膜。