In this study, TaMoCrTiAl refractory high-entropy alloy coating without defects was successfully prepared on the Ti6Al4V substrate by laser metal deposited. Microstructure and properties were investigated systematically by multiple characterization methods. The results of phase and morphology experiments indicate that the coating comprised a BCC phase and a partial Laves phase. The coating, with an average thickness of 990 μm, exhibits good metallurgical bonding with the substrate. Further observation reveals that the cladding region consists of irregular bulk crystals. The heat-affected zone has a fine grain size, whereas the substrate has coarse and uneven grains. The high-temperature oxidation test shows that the formation of an Al2O3 oxide layer enhances the coating's high-temperature oxidation resistance. According to the results of microhardness tests, the average microhardness in the coating is about 570.98 HV (1.87 times that of the substrate) due to the formation of the leave phase particles and the fine-grain strengthening. The presence of Titanium, chromium and molybdenum elements in the coating facilitates the formation of a passivation film, thereby enhancing its corrosion resistance. Furthermore, the coating exhibits the smallest grinding force (43.637 N) and the lowest roughness (0.506 μm) at an experimental temperature of 100 °C, which demonstrates that appropriately elevating the experimental temperature can decrease the grinding force and enhance the flatness of the grinding surface.

中文翻译：

---

激光沉积TaMoCrTiAl耐火高熵涂层的抗氧化性、腐蚀行为及磨削性能


本研究采用激光金属沉积方法在Ti6Al4V基体上成功制备了无缺陷的TaMoCrTiAl耐火高熵合金涂层。通过多种表征方法系统地研究了微观结构和性能。物相和形貌实验结果表明涂层包含BCC相和部分Laves相。涂层平均厚度为990μm，与基体表现出良好的冶金结合。进一步观察表明，包层区域由不规则的块状晶体组成。热影响区晶粒细小，而基体晶粒粗大且不均匀。高温氧化测试表明Al2O3氧化层的形成增强了涂层的高温抗氧化性能。根据显微硬度测试结果，由于留相颗粒的形成和细晶强化，涂层的平均显微硬度约为570.98 HV（基体显微硬度的1.87倍）。镀层中钛、铬、钼元素的存在有利于钝化膜的形成，从而增强其耐腐蚀性能。此外，在100℃的实验温度下，涂层表现出最小的磨削力（43.637N）和最低的粗糙度（0.506μm），这表明适当提高实验温度可以降低磨削力，提高磨削的平整度表面。