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论文类型：期刊论文

发表时间：2013-08-15

发表刊物：8th Asian-European International Conference on Plasma Surface Engineering (AEPSE)

收录刊物：SCIE、EI、CPCI-S、Scopus

卷号：228

期号：SUPPL.1

页面范围：S164-S170

ISSN号：0257-8972

关键字：High-intensity pulsed ion beam; Magnesium alloy AZ31; Microarc oxidation film; Corrosion behavior

摘要：Micro-arc oxidation (MAO) films on AZ31 magnesium alloy were modified by high-intensity pulsed ion beam(HIPIB) irradiation with ion energy of 300keV at 200A/cm(2) with 1-10 shots. A compact and solidified layer was prepared on the irradiated MAO films. The electrochemical impedance spectrum (EIS) of the MAO films in 3.5% NaCl solution was measured with varying the immersion time. The Nyquist plots for EIS showed typical capacitive arc and inductive loop. The diameters for capacitive arc and inductive loop are both increased and then decreased with increasing irradiation shot number, the maximal value for diameters obtained at 200A/cm(2) with 5 shots at immersion time of 5h achieved to 6 x 10(7) Omega and 1.5 x 10(5) Omega, respectively. With immersion time augment, the diameters for capacitive arc and inductive loop of Nyquist plots both decreased. Based on the results of EIS measurements, appropriate equivalent circuits for the modified layers were proposed to fit the EIS for MAO films. It is found that the enhancement in corrosion property of ablated MAO films is mainly caused by improvement of continuity and compaction of films irradiated by HIPIB, which suppressed the corrosion process by holding back the transfer of electrolyte through the modified films to magnesium substrate during immersion. (C) 2012 Elsevier B.V. All rights reserved.