选区激光熔化技术(SLM)制备的(FeCoNi)₈₆Al₇Ti₇高熵合金，经780 ℃退火处理后，深入分析打印态和退火态合金在 0.5mol/L H₂SO₄溶液中的电化学腐蚀性能。通过电化学工作站测试高熵合金的开路电位、交流阻抗与极化曲线，发现退火态(FeCoNi)₈₆Al₇Ti₇高熵合金自腐蚀电位更高，自腐蚀电流密度更低，容抗弧直径更大，阻抗值更高，以及电荷转移电阻更大。X射线光电子能谱(XPS)，分析腐蚀表面钝化膜的成分及含量表明，退火态高熵合金腐蚀表面氧化物的种类更丰富，含量更高，更易形成稳定的钝化膜。结果表明，780 ℃退火处理能显著改善(FeCoNi)₈₆Al₇Ti₇高熵合金的耐腐蚀性能。

In this study, the (FeCoNi)₈₆Al₇Ti₇ high-entropy alloy was prepared by selective laser melting (SLM), and then annealed at 780 °C. Both the as-fabricated and annealed (FeCoNi)₈₆Al₇Ti₇ high-entropy alloys were placed in 0.5 mol/L H₂SO₄ solution for electrochemical corrosion experiments to explore the corrosion performance of the high-entropy alloys under acidic environment. The open circuit potential (OCP), electrochemical impedance spectroscopy (EIS) and polarization curves of high-entropy alloys were measured by electrochemical workstation. It was found that the self-corrosion potential of annealed (FeCoNi)86Al7Ti7 high entropy alloy was higher, the self-corrosion current density was lower. Meanwhile, the capacitive reactance arc diameter was larger, the impedance value was higher, and the charge transfer resistance was larger in comparation with the as-fabricated alloy. X-ray photoelectron spectroscopy (XPS) was used to analyze the composition and content of the passivation film on the corroded surface. The results show that the oxide species on the corroded surface of the annealed high-entropy alloys are richer and the content is higher, and the stable passivation film is easier to be formed. The results show that annealing at 780 °C can significantly improve the corrosion resistance of (FeCoNi)₈₆Al₇Ti₇ high entropy alloys.