Abstract: Aiming at the problem of selecting friction material for water medium hydraulic brake, the friction and wear mechanism of the materials was described. The three kinds of friction material was choosen, such as the widely used iron nickel alloy, copper base powder metallurgical powder and GrMnFeCoNi high entropy alloys.Considering the actual working condition of the shearer, the emergency braking time is set at 0.7 s, the thermal structural coupling and the displacement deformation of the three friction materials were analyzed by using the engineering finite element method.The results show that when the friction material is iron nickel alloy powder, the the highest temperature of brake disc is 263.16 ℃, the maximum amount of the deformation is 8.3921 mm. When the friction material is copper base powder metallurgy, the the highest temperature of the brake disc is 220.9 ℃, the maximum amount of deformation is 9.0192 mm. When the friction material is GrMnFeCoNi series high entropy alloys, the highest temperature of the brake disc is 194.29 ℃, the maximum amount of deformation is 7.554 mm; By contrast, it is determined that GrMnFeCoNi series high-entropy alloys is the best friction material.