Surface phenomenon such as cavitation erosion-corrosion limits the working life and durability of the fluid machines through significantly altering the efficiency. Surface modification is an apparent and economical route for improving the sustainability of these components. Recently developed complex concentrated alloys (CCAs) or high entropy alloys (HEAs) possess exceptional properties owing to high configurational entropy. We developed CCA coatings on the stainless steel using a facial and effective microwave processing technique. The effect of Al molar fraction in Al_xCoCrFeNi (x = 0.1 to 3) CCAs on ultrasonic cavitation erosion-corrosion was investigated in 3.5% NaCl solution. For comparison, cavitation erosion and electrochemical corrosion behavior of the pre- and post- tested samples was also performed. Detailed microstructure and mechanical characterization of the developed coatings were also preformed using different analytical techniques. The equimolar CCA coating showed apical degradation resistance under both pure erosion and erosion-corrosion conditions. The observed behavior is attributed to high strain hardening, optimal hardness, fracture toughness, and utmost stability of the passive layer. The phenomenal conjugation of these properties was associated with highest configurational entropy for equimolar composition resulting in sluggish diffusion, and severe lattice straining. Compared to pits, striations and cracks characterizing the morphology of the degraded stainless steel, the equimolar and Al_0.1CoCrFeNi CCAs showed TTS (tearing topograph surface) as the dominant failure mode characterized by presence of microplastic deformation. The degradation of the Al₃CoCrFeNi CCA occurred mainly through brittle failure mode. The difference in failure mechanism are related with the mechanical properties and underlying microstructure.

空化腐蚀等表面现象会显着改变效率，从而限制了流体机械的使用寿命和耐用性。表面改性是提高这些组件可持续性的一种明显且经济的途径。由于高组态熵，最近开发的复杂浓缩合金（CCA）或高熵合金（HEA）具有出色的性能。我们使用面部和有效的微波加工技术在不锈钢上开发了CCA涂层。Al摩尔分数对Al _x的影响研究了CoCrFeNi（x = 0.1至3）CCAs在3.5％NaCl溶液中对超声空化的腐蚀和腐蚀。为了进行比较，还对测试前和测试后的样品进行了气蚀和电化学腐蚀行为。还使用不同的分析技术对开发的涂层进行了详细的微观结构和力学表征。等摩尔CCA涂层在纯腐蚀和腐蚀腐蚀条件下均显示出抗顶尖降解的性能。观察到的行为归因于钝化层的高应变硬化，最佳硬度，断裂韧性和最大稳定性。这些特性的显着共轭与等摩尔组成的最高构型熵有关，从而导致缓慢的扩散和严重的晶格应变。相比坑_0.1 CoCrFeNi CCAs显示出TTS（撕裂的形貌表面）是主要的破坏模式，其特征是存在微塑性变形。Al ₃ CoCrFeNi CCA的降解主要通过脆性破坏模式发生。破坏机理的差异与机械性能和底层微观结构有关。