表面技术2026，Vol.55Issue(1)：145-156,12.DOI:10.16490/j.cnki.issn.1001-3660.2026.01.013
激光增材制造Nb-30Ti-20W合金在酸碱盐溶液中的室温电化学腐蚀行为
Room-temperature Electrochemical Corrosion Behavior of Nb-30Ti-20W Alloy Fabricated by Laser Additive Manufacturing in Acid,Alkali and Salt Solutions
摘要
Abstract
Due to the high melting point,Nb-based alloys are regarded as an ideal alternative to Ni-based superalloys and the most suitable materials for developing a new generation of turbine blades.Since the turbine blades are expensive,the applied alloys should withstand the test of long service.However,the corrosion resistance of the Nb-based alloys is still insufficient.Thus,the researches on the corrosion resistance of the Nb-based alloys are of great importance.In present work,Nb-30Ti-20W alloy was designed to enhance the performance of the traditional Nb-based alloy.Due to its high melting point and relative high hardness,the Nb-30Ti-20W alloy was hard to be processed by traditional methods.To overcome this shortcoming,the Nb-30Ti-20W samples were prepared by laser melting deposition(LMD)method at argon atmosphere.The LMD prepared Nb-30Ti-20W alloy exhibited a body centered cube(BCC)structure and equiaxed crystals with average grain size of～50 μm.Then,the corrosion rates and mechanisms under different environments of the prepared Nb-30Ti-20W alloy were investigated after grinding and polishing.The open-circuit potential,dynamic polarization curves and alternating current impedance of the alloy in 3.5%NaCl solution,1 mol/L HCl solution,0.5 mol/L H2SO4 solution and 1 mol/L NaOH solution were measured with an electrochemical workstation.After the corrosion test,the morphologies of the corroded surface of the samples and the composition of the passivating membrane components were characterized through X-ray diffraction(XRD),optical microscopy(OM),scanning electron microscopy(SEM)and X-ray photoelectron spectroscopy(XPS).Combined with the analysis of the polarization curves,the alloy was passivated in the four corrosive media.Passivation breakdown only occurred in NaCl solution.The passivating membrane components of the alloy in 3.5%NaCl solution,1 mol/L NaOH solution,1 mol/L HCl solution and 0.5 mol/L H2SO4 solution were all TiO2,Nb2O5 and WO3.The low X-ray photoelectron spectroscopy(XPS)peak intensity of the corrosion products after NaCl corrosion indicated lower oxide content in these products.Cl element was observed in the pitting on the corroded surface in NaCl solution,while it was absent on the uncorroded surface.Based on the reaction principles and the chemical properties of the products,this phenomenon suggested the formation of chlorides such as TiCl3 and NbCl5 in the pitting.The average corrosion rates of the alloy,calculated from the Tafel extrapolation of self-corrosion current density,were 0.017 8 mm/a(NaCl),0.009 7 mm/a(HCl),0.006 2 mm/a(H2SO4)and 0.172 mm/a(NaOH).The polarization resistance Rp value was fitted by fitting the circuit diagram with the AC impedance curve.By combining equivalent circuit fitting of electrochemical impedance spectroscopy(EIS)data with extrapolation of Rp values from potentiodynamic polarization curves,it was indicated that the alloy exhibited significantly lower charge transfer resistance in NaOH solution.The Nb-30Ti-20W alloy demonstrated good corrosion resistance to acid,alkali and saline solutions at room temperature.The alloy formed a passivation film to prevent further reaction.The present work indicates that the Nb-30Ti-20W alloy exhibits excellent corrosion resistance in different environments,and may be a promising candidate for the development of next-generation turbine blade structural materials.关键词
Nb-Ti-W合金/激光增材制造/室温腐蚀/酸碱盐溶液腐蚀/电化学腐蚀评价/化学成分分析Key words
Nb-Ti-W alloy/laser additive manufacturing/room-temperature corrosion/acid-alkali-salt solution corrosion/electrochemical corrosion evaluation/chemical composition analysis分类
矿业与冶金引用本文复制引用
谢增,季亚奇,赵玲,史雁行,梁传辉,刘学..激光增材制造Nb-30Ti-20W合金在酸碱盐溶液中的室温电化学腐蚀行为[J].表面技术,2026,55(1):145-156,12.基金项目
表面物理与化学重点实验室基金(JCKYS2023120204) State Administration of Science,Technology and Industry for National Defense Basic Scientific Research Program(JCKYS2023120204) （JCKYS2023120204）
