Abstract

In this paper, to improve the hardness and wear resistance, AlCoCrFeNiSi HEA coatings were synthesized on AISI 304 stainless steel by laser cladding. The microstructure, chemical composition, constituent phases, microhardness, wear resistance and corrosion resistance of the coating were analyzed by scanning electron microscopy (SEM), energy-dispersive spectrometer (EDS), x-ray diffraction (XRD), Vickers microhardness tester, pin-on-disk tribological tester and electrochemical workstation, respectively. The experimental results showed that the coating possessed a single body-centered cubic (BCC) phase structure (Fe-Cr). Si element was dissolved into Fe-Cr solid solution, resulting in severe lattice distortion. The dislocation density of the coating was as high as 1.07 × 10¹⁴ m⁻². Therefore, the microhardness (630.36 HV_0.3) of the HEA coating was significantly improved by the effect of solid solution strengthening and dislocation strengthening. The coating exhibited excellent wear resistance, and abrasive wear was effectively avoided. The wear mechanism of the coating involved mainly oxidation wear and slight adhesion wear. The corrosion resistance of the coating was better than that of AISI 304 stainless steel in 3.5% NaCl solution. In conclusion, the AlCoCrFeNiSi HEA coating prepared by laser cladding can provide excellent wear protection to stainless steel at no expense to its own corrosion resistance.

中文翻译：

---

AISI 304不锈钢激光熔覆AlCoCrFeNiSi高熵合金涂层的组织与性能

摘要

为了提高硬度和耐磨性，本文通过激光熔覆在AISI 304不锈钢上合成了AlCoCrFeNiSi HEA涂层。通过扫描电子显微镜（SEM），能量色散光谱仪（EDS），X射线衍射（XRD），维氏显微硬度测试仪，销钉分析了涂层的微观结构，化学成分，组成相，显微硬度，耐磨性和耐蚀性磁盘摩擦测试仪和电化学工作站。实验结果表明，该涂层具有单一的体心立方（BCC）相结构（Fe-Cr）。Si元素溶解在Fe-Cr固溶体中，导致严重的晶格畸变。涂层的位错密度高达1.07×10 ¹⁴  m ^-2。因此，固溶强化和位错强化的效果显着提高了HEA涂层的显微硬度（630.36 HV _0.3）。涂层表现出优异的耐磨性，有效避免了磨料磨损。涂层的磨损机理主要包括氧化磨损和轻微的粘附磨损。在3.5％NaCl溶液中，涂层的耐腐蚀性优于AISI 304不锈钢。总之，通过激光熔覆制备的AlCoCrFeNiSi HEA涂层可以为不锈钢提供出色的耐磨保护，而无需牺牲其自身的耐腐蚀性。