摘要
采用电化学噪声技术,结合电化学阻抗谱及极化曲线测量,研究了峰时效AA2195-T8铝合金在3.0%NaCl溶液中的腐蚀电化学特征.结果表明,腐蚀初期,合金表面钝化膜上不断有孔核的形成与修复,并导致阻抗谱上感抗成分的存在.随腐蚀时间的延长,其感抗成分消失且阻抗模值降低.阳极极化时,由于其孔蚀电位与自腐蚀电位接近,钝化电位区间很小;随腐蚀时间的延长,极化电阻先增加而后减小,自腐蚀电流则呈相反趋势变化.
The electrochemical features of the corrosion of AA2195-T8 aluminum alloy in 3.0% NaCl solution were studied by electrochemical noise(EN) technique, electrochemical impendence spectroscopy(EIS) and potentiodynamic scanning(PDS). At the initial stage, the pitting cores are formed. and the passive film is repaired continuously, which results in the inductive component in the electrochemical impendence spectrum. With prolonging the immersion time, the inductive component is disappeared gradually, and the impendence module is decreased largely. The passive region is very small, due to the little difference between pitting corrosion potential (E-pit) and self-corrosion potential (E-corr,). The polarization resistance (R-p) is increased and then decreased as the immersion time is prolonged, the self-corrosion current is changed in the form of reverse tend.
出处
《金属学报》
SCIE
EI
CAS
CSCD
北大核心
2002年第7期760-764,共5页
Acta Metallurgica Sinica
基金
国家自然科学基金50071054
国家重点基础研究发展规划基金资助G19990650项目
关键词
AA2195-T8铝合金
NACL溶液
腐蚀
电化学噪声
阻抗谱
极化曲线
AA2195-T8 aluminum alloy
NaCl solution
corrosion
electrochemical noise(EN)
electrochemical impendence spectroscopy(EIS)
potentiodynamic scanning(PDS)