AlCoCrCuFe高熵合金的组织结构与摩擦磨损性能

High entropy alloy has broken through the design idea of traditional alloy with one or two main elements, and has a simple solid solution structure formed by various of alloying elements (≥ 5) with the nearly equal mole ratio. Owing to its excellent performance, high entropy alloy may open the door of the performance limit of traditional metal materials and meet higher demand for materials in the development of industrial technology. AlCoCrCuFe high-entropy alloy was fabricated by non-consumable arc remelter, and the mechanism of phase formation among the multi principal alloy element and the effect of its microstructure on the friction and wear properties were studied.The microstructure, phase structure and wear resistance of AlCoCrCuFe were investigated by XRD, SEM, EDS, microhardness tester and friction-wear tester. The results showed that AlCoCrCuFe alloy has typical dendrite structure and BCC+FCC dual phase having broaden diffraction peaks. The friction coefficient of AlCoCrCuFe/GCr15 increases at first and then decreases and stabilize with the increase of friction time, and the wear mechanism changes from delamination wear to oxidative wear under the condition of dry friction. The average friction coefficient is 0.55, and the mass loss rate is 1.44 %. The reason of Cu-rich intergranular region is due to the difference of mixing enthalpy, binding capacity, solubility and melting point between Cu and other elements. The layered grid structure of spinodal decomposition is owing to the influence of coherent stress and elastic interaction caused by atomic size in dendrite region. The precipitation of nanoparticles near the dendritic boundary is determined by hysteresis diffusion effect, metal heredity and process. The difference of each component in atomic radius, mole ratio and mixing enthalpy, large residual stress and small crystalline grain results in the broaden diffraction peaks of BCC phase and FCC phase.