Brake disc is one of the important factors to ensure the safety of high-speed train.In the process of long-term operation, the high-speed train fails due to friction and wear and thermal mechanical fatigue.In extreme weather, such as sandstorm in Northwest China, it will cause serious abnormal wear to the brake disc, and even reduce the wear resistance, greatly reducing the service life of the brake disc.Therefore, surface strengthening technology has important application value.Due to the characteristics of rapid cooling, rapid heating and rapid solidification, laser cladding can effectively improve the nucleation rate and refine the grain, overcome the problem of composition segregation in conventional coating manufacturing, and greatly improve the performance of the coating.In this paper, high entropy alloy coatings(HEAs) with different B and Si contents were prepared by laser cladding. The phase and organizational appearance of different coatings were studied, and the wear resistance and thermal mechanical fatigue properties were studied.The contents that we were devoted to are as follows:

1.With the addition of Si content, the friction coefficient firstly decreases and then increases to the maximum.When Si content reaches the highest, that is  Fe₁₀Co₁₀Ni₁₀Cr₄Mo₆B₀Si₁₀ , the hardness is also the highest. It is concluded that there is no direct relationship between the friction coefficient and hardness.

2.When the content ratio of Fe₁₀Co₁₀Ni₁₀Cr₄Mo₆B₅Si₅, the friction coefficient is the smallest.XRD analysis shows that with the increase of Si content, the phase changes from FCC phase to BCC phase.Compared with the original matrix, the friction coefficient is increased from 0.38 to 0.45 and the wear loss is greatly reduced.After remelting process, it is found that the grain size can be refined and the friction and wear properties of Fe₁₀Co₁₀Ni₁₀Cr₄Mo₆B₅Si₅ can be greatly improved.