【摘要】 通过在植酸基础转化液中添加两种不同组成的成膜促进剂制备镁合金植酸转化膜,采用SEM、EDS及失重法研究了添加剂对转化膜结构、形貌及耐蚀性能的影响。结果表明:经植酸转化处理后,镁合金表面耐蚀性能均得到了大幅提高,120h盐水浸泡后失重率仅为镁合金基材的1/5;Ca(NO3)2、NH4VO3及Na2C4H4O6·2H2O组合添加剂的加入有利于改善膜层结构和致密性,转化膜由完整、致密且与基材结合紧密的内层和网纹的外层组成,耐蚀性能较纯植酸转化膜提高1倍,而NaF、Na2B4O7及Na2C4H4O6·2H2O的组合添加剂则对转化膜结构和耐蚀性能影响不显著。更多还原

【Abstract】 Two different kinds of phytic acid conversion coatings on magnesium alloy were prepared in phytic acid base conversion solution with accelerants.The effect of additives on the structure,morphology and corrosion resistance of conversion coating were investigated by SEM,EDS and weight loss method,respectively.The results show that the magnesium alloy surface corrosion performance is improved substantially through phytic acid conversion treatment,and the weight loss of conversion coating is only 1/5of the magnesium alloy substrate after 120hsaline soaking.The structure and compactness of conversion coating are greatly improved by adding Ca(NO3)2,NH4VO3and Na2C4H4O6·2H2O,as the conversion coating consists of inner layer which is combined with the substrate compactly and outer layer which exhibits overlapping curve.The corrosion resistance of corversion coating increases 100%compared to pure phytic acid conversion coating.However,other additives such as NaF,Na2B4O7and Na2C4H4O6·2H2O have no significant impact on structure and corrosion resistance of phytic acid conversion coating.更多还原