摘要
通过对铸造Al-14Si-5Cu-3Ni-1Mg-0.5Mn合金微弧氧化不同厚度陶瓷层的的交流阻抗图谱和塔菲尔曲线的电化学研究,定量分析了陶瓷层的耐蚀性,并用失重法对电化学测试结果进行了进一步验证。利用扫描电镜(SEM)研究了陶瓷层表面微观结构对其耐蚀性的影响。结果表明,微弧氧化可显著提高该合金的电化学阻抗及自腐蚀电位,降低腐蚀电流。微弧氧化陶瓷层特有的微观组织结构是其耐蚀性提高的主要原因,陶瓷层的厚度也是影响其耐蚀性的一个重要因素,但厚度的增加并不一定能提高其耐蚀性。
Corrosion resistance of the ceramic coating formed by micro-arc oxidation (MAO) on a cast Al-14Si-5Cu-3Ni-1Mg alloy was examined with electrochemical methods as EIS and polarization curves, which was further validated by agravity. Effects of surface microstructure of ceramic coating on its corrosion resistance were observed by SEM (scanning electronic microscope). The results reveal that MAO can remarkably improve the corrosion resistance of the aluminum alloy as a result of increasing the EIS and corrosion rate and decreasing the corrosion current. The improvement of corrosion resistance of the ceramic coating is closely dependent on the special microstructure and thickness, however, which is not always improved with the increase of thickness of the coating.
出处
《特种铸造及有色合金》
CAS
CSCD
北大核心
2008年第7期557-559,共3页
Special Casting & Nonferrous Alloys
作者简介
郭巧琴,女,1979年出生,讲师,西安工业大学材料与化工学院,西安(710032),电话:029—83208080,E—mail:guoqiaoqin66@126.com