应用扫描微电极技术和扫描电子显微镜技术研究Al2024-T3合金在NaCl溶液中开路状态下的局部腐蚀发生的早期过程.实验表明,当Al合金浸入NaCl溶液,其表面即刻发生局部微点腐蚀,这些微点腐蚀与合金表面第二相颗粒密切相关,Al合金表面第二相Al2CuMg颗粒可表现为三种不同的腐蚀行为.The scanning microreference electr ode(SMRE)technique and scanning electron mic roscopy(SEM)were applied to investigate the loca lized corrosion in its early stage of Al 2024-T3alloy.SMRE potential measure-ments revealed that localized corro sion occurred on the alloy surface im mediately after the exposure to 0.01mol ·L-1 NaCl solution at open-circuit poten tial,which was more negative than th e pitting potential.The potential peaks developed with time and reached the maximum after 2h exposure.Consequen tly,the heights of potential peaks would decrease and then maintained a stable value for a long time.SEM indi cated the initial of localized corro sion was associated with the second phase particles,especially the Al 2 CuMg (S phase).Three types of corrosion be-havior of S phase were observed.国家自然科学基金(59871043)资助项
