Corrosion properties of AlxCoCrFeNiTi0·5 high entropy alloys in 0·5M H2SO4 aqueous solution
Corrosion properties of AlxCoCrFeNiTi0·5 high entropy alloys in 0·5M H2SO4 aqueous solution
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DOI：
10.1179/1432891714z.000000000778
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发表时间：
2014-07
影响因子：
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通讯作者：
J. Zhang;X. Yin;Y. Dong;Y. Lu;L. Jiang;T. Wang;T. Li
中科院分区：
文献类型：
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作者：
J. Zhang;X. Yin;Y. Dong;Y. Lu;L. Jiang;T. Wang;T. Li
摘要在以往的研究中，不同铝含量的AlxCoCrFeNiTi 0·5高熵合金显示出许多优异的力学性能，但很少有人尝试对其耐腐蚀性能进行研究。因此，本文通过动电位扫描、腐蚀表面形貌和交流阻抗谱分析，研究了AlxCoCrFeNiTi 0·5（x = 0，0·5，1·0）合金体系在0·5M H2SO4水溶液中的腐蚀行为。结果表明，高含量的Al提高了合金的腐蚀电位，降低了腐蚀电流密度，抑制了点蚀倾向，从而提高了合金的耐蚀性。当x = 0·5和1时，合金的腐蚀性能优于304不锈钢。根据交流阻抗测试结果，得到了等效电路。结果表明，钝化膜的存在和扩散困难是影响电化学反应过程的重要因素。该研究还表明，0.75 V的恒电位处理明显提高了合金的耐腐蚀性。
Abstract In previous research, AlxCoCrFeNiTi0·5 high entropy alloys with various amounts of aluminium had shown many excellent mechanical performances, but few attempts were made to characterise the corrosion performance. Therefore, the purpose of this study was to investigate that of the AlxCoCrFeNiTi0·5 (x = 0, 0·5, 1·0) alloy system in an aqueous solution of 0·5M H2SO4 at room temperature with the analysis of potentiodynamic polarisation scanning, corrosion surface morphology and electrochemical impedance spectra. It was verified that a high content of Al enhanced the corrosion resistance of the alloys by simultaneously increasing the corrosion potential and decreasing the corrosion current density, also restraining the tendency of pitting corrosion. When x = 0·5 and 1, the alloys had a better corrosion behaviour compared with 304 stainless steel. The equivalent circuits were obtained from the results of EIS tests. They clearly revealed that the existence of a passive film and the difficulty of the resultant diffusion were both important factors to the electrochemical reaction process. This study also demonstrated that constant potential treatment at 0·75 V clearly enhances the corrosion resistance of the alloys.