【摘要】 采用激光熔覆工艺在Q235钢表面制备了Al₂CrFeCoCuNi_xTi高熵合金涂层,分析了Al₂CrFeCoCuNi_xTi高熵合金涂层的组织结构,测试了Al₂CrFeCoCuNi_xTi高熵合金涂层在0.5 mol/LHNO₃溶液及0.5 mol/L HCl溶液中的耐蚀性能。结果表明:Al₂CrFeCoCuNi_xTi高熵合金涂层主要分为熔覆区、结合区、热影响区,熔覆区组织主要由等轴晶组成,等轴晶上分布有微米尺度的粒子;合金相结构简单,由体心立方（BCC）及面心立方（FCC）结构组成;Cr元素和Ni元素的钝化作用及由Al元素形成Al₂O₃或Al₂O₃·H₂O膜使得Al₂CrFeCoCuNi_xTi高熵合金涂层在0.5 mol/L HNO₃溶液及0.5 mol/L HCl溶液中具有较好的耐蚀性能,自腐蚀电流密度与基体Q235钢相比降低一两个数量级;0.5 mol/L HCl溶液中的Cl-会穿透Ni_0.5高熵合金涂层表面形成的钝化膜,出现轻微小孔腐蚀。更多还原

【Abstract】 The Al₂ CrFeCoCuNi_xTi high entropy alloy coating was prepared by laser cladding on Q235 steel surface. The microstructure of Al₂ CrFeCoCuNi_xTi high entropy alloy coatings were analyzed, and the corrosion resistance of Al₂ CrFeCoCuNi_xTi high entropy alloy coatings in 0.5 mol/L HNO₃ solution and0.5 mol/L HCl solution were tested. The experimental results show that the Al₂ CrFeCoCuNi_xTi high entropy alloy coating can be divided into cladding zone, bonding zone and heat affected zone. The microstructure of cladding zone is mainly composed of equiaxed grain, with micron-grade particles distributed on it, the phase structure of Ni1.0 high entropy alloy coating was simple for FCC andBCC structure. Due to the passivation effect of Cr and Ni elements and formation of Al₂ O₃ and Al₂ O₃·H₂ O films by Al element, the Al₂ CrFeCoCuNi_xTi high entropy alloy coating exhibits good corrosion resistance in 0.5 mol/L HNO₃ solution and 0.5 mol/L HCl solution. Compared with Q235 steel, the corrosion current density decreases 1-2 orders of magnitude. Pitting corrosion appears because of Cl-in 0.5 mol/L HCl solution can penetrate the passive film on the Ni_0.5 high entropy alloy coating surface.更多还原