Abstract Through electroless plating, the Al0.3CoCrFeNi high-entropy alloys were successfully coated with the Ni-P amorphous film with a thickness of 1.2 μm. For studying the surface change of samples after chemical plating, the surface morphologies of the as-cast HEA substrate and HEA with the Ni-P film were contrasted by atomic-force microscopy. The tensile properties of the samples with and without the Ni-P film, and the deformational behavior of thin Ni-P film were researched, respectively. In addition, the effect of the Ni-P amorphous film on corrosion resistance of the coated HEAs was also investigated. The experimental results show that in contrast to the uncoated samples with a yielding strength of 275 MPa, the yielding strength of the coated samples exhibits 400 MPa, with a 45% improvement, which can be attributed to the very high yield strength of the Ni-P amorphous film. A tensile strain up to 10% was achieved in the Ni-P film since the propagation of one primary shear band was inhibited, and the stress/strain concentration was retarded by the plastic substrate. The corrosion resistance of the HEA with the Ni-P film is superior to that of the bare HEA in the 3.5 wt percent NaCl solutions due to the chemical homogeneity and the absence of microscopic defects in the Ni-P amorphous film. The current results indicate that the surface coating is an effective means for optimizing the properties of HEAs, and the thin Ni-P coating can remarkably improve the strength of the present HEAs.

中文翻译：

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Ni-P非晶薄膜对Al 0.3 CoCrFeNi高熵合金力学和腐蚀性能的影响

摘要 通过化学镀，Al0.3CoCrFeNi 高熵合金成功包覆了厚度为1.2 μm 的Ni-P 非晶薄膜。为了研究化学镀后样品的表面变化，通过原子力显微镜对比铸态 HEA 基板和带有 Ni-P 膜的 HEA 的表面形貌。分别研究了含和不含 Ni-P 膜的样品的拉伸性能和薄 Ni-P 膜的变形行为。此外，还研究了 Ni-P 非晶膜对涂层 HEA 耐腐蚀性的影响。实验结果表明，与未涂层试样的屈服强度为 275 MPa 相比，涂层试样的屈服强度为 400 MPa，提高了 45%，这可以归因于 Ni-P 非晶膜的非常高的屈服强度。由于一个主剪切带的传播被抑制，并且应力/应变集中被塑料基板阻滞，因此在 Ni-P 膜中实现了高达 10% 的拉伸应变。由于 Ni-P 非晶膜中的化学均匀性和不存在微观缺陷，具有 Ni-P 膜的 HEA 的耐腐蚀性优于 3.5 wt% NaCl 溶液中的裸 HEA。目前的结果表明，表面涂层是优化 HEA 性能的有效手段，薄的 Ni-P 涂层可以显着提高现有 HEA 的强度。并且应力/应变集中被塑料基板延迟。由于 Ni-P 非晶膜中的化学均匀性和不存在微观缺陷，具有 Ni-P 膜的 HEA 的耐腐蚀性优于 3.5 wt% NaCl 溶液中的裸 HEA。目前的结果表明，表面涂层是优化 HEA 性能的有效手段，薄的 Ni-P 涂层可以显着提高现有 HEA 的强度。并且应力/应变集中被塑料基板延迟。由于 Ni-P 非晶膜中的化学均匀性和不存在微观缺陷，具有 Ni-P 膜的 HEA 的耐腐蚀性优于 3.5 wt% NaCl 溶液中的裸 HEA。目前的结果表明，表面涂层是优化 HEA 性能的有效手段，薄的 Ni-P 涂层可以显着提高现有 HEA 的强度。