电子束蒸发制备高熵合金涂层AlxFeCoCrNiCu(x = 0.25, 0.5 and 1.0)的微观结构和耐腐蚀性能研究

Microstructure and corrosion properties of AlxFeCoCrNiCu(x = 0.25, 0.5 and 1.0) thin coatings on steel substrates deposited by electron beam evaporation

摘要:

实验采用电子束蒸发法在钢基体表面制备高熵合金涂层，探究不同Al 元素对微观结构、表面形貌和电化学性能的影响。涂层表面的X射线、电子探针和原子力显微镜实验结果表明，不同成分的合金涂层均呈典型的树枝晶结构，组织中仍保持原有的化学组成。涂层表面平整分布均匀，膜层致密。在0.5 mol/L H2SO4 溶液和 1 mol/L NaCl 溶液中，高熵合金的宽钝化区大于700mV，具有较大的腐蚀电势-129mV和较小的腐蚀电流密度约2.2×10-6 A/cm2，Al0.5FeCoCrNiCu 涂层的耐蚀性最佳。

Abstract:

High entropy alloy (HEA) thin coatings have been deposited on steel substrate of a mixed alloy power made of high purity elemental aluminium, cobalt, chromium, copper, iron and nickel by electron beam evaporation and effect of the Al content of the coating on its structural, surface morphology and electrical properties were investigated. The results of X-ray diffraction (XRD) showed that coatings were typical dendrite and interdendrite structures with different aluminum contents. The coatings’ surface chemistry components were basically similar composition as originally designed alloys by electron probe micro-analyzer (EPMA). Atomic force microscopy (AFM) indicated that modified the surface of all coatings were very smooth and uniform. HEA coatings exhibited wide passive regions, which extended ＞700 mV in aqueous solutions of H2SO4 and NaCl. A large corrosion potential (-129 mV) and a small corrosion current density (≈2.2×10-6 A/cm2) clearly revealed that the corrosion resistance of the Al0.5FeCoCrNiCu coating was superior to that of the coatings.