摘要
研究了AZ91D镁合金的锡酸盐化学转化表面处理工艺,利用中性盐雾试验和极化曲线法测试了转化膜的耐蚀性,使用划格法测试了转化膜对有机涂层的附着力,采用扫描电镜、能谱仪、射线衍射仪分析了转化膜的微观形貌、成分和结构并讨论了成膜机理。结果表明,最佳工艺条件下的锡酸盐转化膜为致密的MgSnO3·3H2O晶粒所构成,盐雾腐蚀评级达到了8级,自腐蚀电位降低了40mV,对铁红漆的附着力达到了3B级。
The stannate chemical conversion surface treatment techniques for AZ91D magnesium alloy were investiga- ted. The anti-corrosion ability of conversion coatings were tested by NSS and polarization curve methods. The adhesive force of conversion coatings to organic coats was tested by lattice methods. The microtopography, elements, structure and possible conversion mechanism were analyzed by SEM, EDS and XRD. The results show that the stannate chemical con- version coating is composed of compact MgSnO3 ~ 3H20 grains, its NSS grade is 8, its corrosion potential is 40 mV low- er than that of the original magnesium alloy, its adhesive force grade to iron red paint coating is 3B.
出处
《金属热处理》
CAS
CSCD
北大核心
2008年第8期89-92,共4页
Heat Treatment of Metals
基金
南京工程学院科研基金项目(KXJ07009)
关键词
镁合金
表面处理
化学转化
锡酸盐
magnesium alloy
surface treatment
chemical conversion
stannate -
