感应重熔合成AlCo_(x)CrFeNiCu高熵合金涂层的组织与耐腐蚀性能

采用冷喷涂辅助感应重熔合成不同Co含量的AlCo_(x)CrFeNiCu(x=0、0.5、1、1.5、2)高熵合金涂层。通过XRD、SEM、EDS、电化学工作站等设备检测分析了不同Co元素含量AlCo_(x)CrFeNiCu高熵合金涂层的相结构、微观组织、耐腐蚀性能等。结果表明:高熵合金涂层的相结构为FCC+BCC双相混合结构,微观组织形貌为枝晶+枝晶间组织,随着Co含量的增加,AlCo_(x)CrFeNiCu系高熵合金涂层中的枝晶数目增加,并明显粗化。面扫描分析表明显微组织中枝晶内富集Fe、Cr、Co元素,枝晶间富集Cu元素,Al均匀的分布在整个涂层中。在3.5%NaCl腐蚀介质中,AlCo 0.5 CrFeNiCu高熵合金涂层更耐腐蚀,比其他比例Co含量涂层有较正的自腐蚀电位(E_(corr)=-0.37 V)和较小的自腐蚀电流密度(I_(corr)=4.9×10^(-6)A/cm^(2))。

Induction Remelting Synthesis of AlCoxCrFeNiCu High-entropy AlloyCoating Organization and Corrosion Resistance

AlCoxCrFeNiCu (x=0, 0.5, 1, 1.5, 2) high entropy alloy coatings with different Co contents were synthesized by cold spray assisted induction remelting. The effects of microstructure, phase structure and corrosion resistance of the AlCoxCrFeNiCu high-entropy alloy coatings with different Co element contents were analysed by XRD, SEM, EDS and electrochemical workstation tests. The microstructure of the high-entropy alloy coating is dendritic + interdendritic, and the phase structure is FCC + BCC biphasic mixed structure. The microstructure was analysed by surface sweeping. The dendrites were enriched with Fe, Cr and Co elements, the dendrites were enriched with Cu elements , and Al was uniformly distributed throughout the coating. The AlCo0.5CrFeNiCu high-entropy alloy coating is more resistant to corrison in 3.5 wt.% NaCl corrosive media and has a more positive self-corrosion potential (Ecorr = -0.37 V) and a lower self-corrosion current density (Icorr = 4.9 × 10-6 A?cm-2) than other coatings with proportional Co content.