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所属单位：材料科学与技术学院

发表刊物：APPLIED SURFACE SCIENCE

关键字：Tantalum silicides Mechanical properties Electrochemical impedance Corrosion

摘要：In this study, the effects of Ti substitutional additions on the mechanical and electrochemical corrosion behavior of beta-Ta5Si3 were investigated through both theoretical calculation and experiment. Initially, first-principles calculations, based on density functional theory, were used to guide compositional design, according to the calculation of mechanical parameters (for example, bulk modulus, shear modulus, Young's modulus, the shear modulus/bulk modulus ratio and Poisson's ratio). This analysis showed that optimum mechanical performance may be achieved through Ta atoms in the Ta20Si12 unit cell being replaced by two Ti atoms. Subsequently, both the binary beta-TasSi(3) coating and the optimized Ti-alloyed beta-Ta5Si3 coating (i.e., beta-(Ta0.902Ti0.098)(5)Si-3) were deposited onto Ti-6AI-4V substrates using a double cathode glow discharge plasma method. Both as-deposited coatings exhibited a tetragonal crystal structure with fine equiaxed grains similar to 4 nm in diameter. The mechanical properties of the coatings were determined by both nanoindentation and Vickers indentation techniques, and their electrochemical corrosion behavior was examined by potentiodynamic polarization, electrochemical impedance spectroscopy (EIS) and Mott-Schottky analysis in naturally aerated 0.9 wt.% NaCl solution at 37 degrees C. These investigations showed that the addition of Ti significantly improved the damage resistance of beta-Ta5Si3, with little negative impact on its corrosion resistance. (C) 2017 Elsevier B.V. All rights reserved.

ISSN号：0169-4332

是否译文：否

发表时间：2017-10-15

合写作者：陈建,Jiang, Shuyun,Munroe, Paul,Xie, Zong-Han

通讯作者：徐江