The refractory high-entropy alloys (RHEAs) possess excellent mechanical properties and electron beam cladding (EBC) has the advantages of vacuum protection and higher energy utilization. In this study, the Mo₂₀Nb₂₀Co₂₀Cr₂₀(Ti₈Al₈Si₄) RHEA coatings under different cladding currents (16, 17, 18,19 mA) are fabricated by EBC to improve the surface wear resistance of the Ti600 substrate. The microstructure and phase structure of RHEA coatings are investigated by OM, SEM, XRD, TEM. The mechanical properties of tcoatings and substrate are studied by microhardness, nanoindentation and dry wear test. The results show that the HEA coatings involve four main phases: BCC1(Mo,Nb,Al-rich-A2/B2), BCC2(Co,Cr,Ti-rich-B2), IMC1(Laves phase-CoTi) and IMC2((Ti,Nb,Zr)₅Si₃), respectively. With the cladding current increasing, the dilution rate of the substrate increases to cause the Ti content within coatings to rise. The size of BCC1(DR regions), IMC1 and IMC2 becomes larger and the microhardness, nanoindentation hardness, elastic modulus and room-temperature creep resistance decrease. The properties improvement of the coating is attributed to the solid solution, second phase and precipitation strengthening caused by the solid solution structures and intermetallic compounds. The maximum microhardness of the coatings at current 16 mA is 1150 HV_0.2, more than 3 times that of the substrate and the friction coefficient of Ti600 is 2.16 times that of current 16 mA, which suggests that the Mo₂₀Nb₂₀Co₂₀Cr₂₀(Ti₈Al₈Si₄) RHEAs can be used as an excellent wear-resistant coating with broad application prospect.

难熔高熵合金（RHEAs）具有优异的力学性能，而电子束熔覆（EBC）具有真空保护和更高能量利用率的优点。在本研究中，Mo ₂₀ Nb ₂₀ Co ₂₀ Cr ₂₀ (Ti ₈ Al ₈ Si ₄) 采用 EBC 制造不同熔覆电流（16、17、18、19 mA）下的 RHEA 涂层，以提高 Ti600 基材的表面耐磨性。采用OM、SEM、XRD、TEM等手段研究了RHEA涂层的显微组织和相结构。通过显微硬度、纳米压痕和干磨损试验研究了涂层和基体的力学性能。结果表明，HEA涂层涉及四个主要相：BCC1(Mo,Nb,Al-rich-A2/B2), BCC2(Co,Cr,Ti-rich-B2), IMC1(Laves phase-CoTi)和IMC2( (Ti,Nb,Zr) ₅ Si ₃）， 分别。随着熔覆电流的增加，基体的稀释率增加，导致镀层内的钛含量增加。BCC1(DR区)、IMC1和IMC2尺寸变大，显微硬度、纳米压痕硬度、弹性模量和室温抗蠕变性降低。涂层性能的改善归因于固溶体结构和金属间化合物引起的固溶强化、第二相强化和析出强化。在电流 16 mA 时涂层的最大显微硬度为 1150 HV _0.2，是基体的 3 倍以上，Ti600 的摩擦系数是电流 16 mA 的 2.16 倍，这表明 Mo ₂₀ Nb ₂₀ Co ₂₀ Cr₂₀ (Ti ₈ Al ₈ Si ₄ ) RHEAs可作为优良的耐磨涂层，具有广阔的应用前景。