【摘要】 应用X射线光电子能谱(XPS)和第一性原理计算的方法研究了纳米化对Fe20Cr合金在Cl-浓度为0.1 mol/L的硼酸缓冲溶液中Cl-吸附行为的影响。结果表明,Cr对Cl-吸附行为有两方面的影响:根据理论计算结果,随着界面处Cr元素含量的增加Cl-的吸附能逐步降低,易于Cl-的吸附;但是在实际环境中Cr含量的增大导致合金更易于形成Cr氧化物的钝化膜,从而阻止Cl-的吸附行为。纳米化加速了Cr元素的扩散行为,导致Cr元素在钝化膜内及钝化膜/金属界面的富集。由此可见,纳米化抑制了Cl-吸附及在钝化膜内的扩散行为,提高了钝化膜的耐蚀能力。更多还原

【Abstract】 The effect of nanocrystallization on the adsorption of Cl-on Fe20 Cr alloy in [Cl-] =0.1 mol/L borate buffer solution was investigated by means of X-ray photoelectron spectrum(XPS) and calculations per the first-principles. The results show that the influence of Cr on Cl-adsorption behavior could be described as the following two aspects : the one, in view of the calculation per the first-principles, is that the adsorption energy decrease with the increasing Cr content at the interface of passive film/alloy, which is conducive to the adsorption of Cl-; the other is that the Cr enrichment may also facilitate the formation of passivation film, which inhibit the Cl-adsorption. Nanocrystallization may enhance the diffusivity of Cr,which leads to the enrichment of Cr within the passive film as well as at the interface of passive film/alloy.Thus, nanocrystallization can inhibit the adsorption and the inward migration of Cl-, and finally enhance the corrosion resistance of the alloy.更多还原