CAJ | 학술논문

为了研究激光冲击强化对镁合金表面形貌和电化学腐蚀性能的影响，采用电化学方法和钕玻璃脉冲激光(波长1064 nm，脉冲宽度20 ns)研究AZ31热轧板和AZ91-T6铸造镁合金在3.5%NaCl(质量分数)溶液中的动态极化曲线和电化学阻抗谱特征，并对镁合金三维表面形貌、腐蚀试样宏观形貌、自腐蚀电位和电化学阻抗谱进行测试与分析。结果表明：激光冲击改善AZ31热轧板和AZ91-T6镁合金的耐蚀性。当激光功率密度处于0.6~0.9 GW/cm2区间，镁合金腐蚀电位和电流密度分别出现峰值和谷值；当功率密度不小于1.0 GW/cm2时，镁合金腐蚀电位和电流密度分别正负移动，与冲击表面的形变、钝化膜和形貌密切相关。
위료연구격광충격강화대미합금표면형모화전화학부식성능적영향，채용전화학방법화녀파리맥충격광(파장1064 nm，맥충관도20 ns)연구AZ31열알판화AZ91-T6주조미합금재3.5%NaCl(질량분수)용액중적동태겁화곡선화전화학조항보특정，병대미합금삼유표면형모、부식시양굉관형모、자부식전위화전화학조항보진행측시여분석。결과표명：격광충격개선AZ31열알판화AZ91-T6미합금적내식성。당격광공솔밀도처우0.6~0.9 GW/cm2구간，미합금부식전위화전류밀도분별출현봉치화곡치；당공솔밀도불소우1.0 GW/cm2시，미합금부식전위화전류밀도분별정부이동，여충격표면적형변、둔화막화형모밀절상관。
In order to study the effect of laser shock processing (LSP) on the surface morphology and electrochemical corrosion resistance of magnesium alloys, the dynamic polarization curves and electrochemical impedance spectroscopy (EIS) of specimens of hot rolled sheet of AZ31 alloy and AZ91-T6 cast alloy in 3.5%NaCl (mass fraction) solution were investigated by electrochemical method and Nd:glass laser with the wavelength of 1064 nm and pulse width of 20 ns. The 3D surface morphology, macroscopic morphology of corrosion specimens, corrosion potential and electrochemical impedance spectroscopy (EIS) were also examined and analyzed. The results show that the corrosion resistance of hot rolled AZ31 alloy sheet and AZ91-T6 cast alloy are improved by LSP. When the laser power density is in the range from 0.6 GW/cm2 to 0.9GW/cm2, the peaks and valleys of the corrosion potential and the current density of magnesium alloy appear, respectively. When the power density is not less than 1.0 GW/cm2 , the corrosion potential and current density of magnesium alloy begin to move towards positive and negative directions, respectively, which are closely related to the deformation, passivating film and morphology of the impact surface.