摘要
通过化学转化的方法在镁合金表面制备出具有优良性能的磷酸盐转化膜。通过单因素试验,得出最优工艺方案为:磷酸氢二钠25g/L,硝酸锌5g/L,氯化钙1g/L,亚硝酸钠4g/L,氟化钠1.5g/L,pH值2,温度55℃,时间30min。最优工艺方案下得到的磷酸盐转化膜的耐蚀性较好,耐蚀时间达到35.91s,其自腐蚀电位比镁合金基体的向负方向移动了0.3V。磷酸盐转化膜表面存在一些裂纹,若要制备更优的磷酸盐转化膜,需对其进行封闭处理。
Phosphate conversion film with excellent performances was prepared on the surface of magnesium alloy by chemical conversion method. The optimum process scheme, which was determined by single factor experiment, was as follows, sodium hydrogen phosphate 25 g/L, zinc nitrate 5 g/L, calcium chloride 1 g/L, sodium nitrite 4 g/L, sodium fluoride 1.5 g/L, pH value 2, temperature 55℃ and time 30 min. The phosphate conversion film obtained with the optimum process scheme exhibit excellent corrosion resistance, the corrosion resistance time reach 35.91 s, and the self-corrosion potential move to negative direction about 0.3 V compared with that of magnesium alloy matrix. Some cracks was found on the surface of phosphate conversion film, and sealing treatment was needed in order to prepare phosphate conversion film with much better morphology and performances.
出处
《电镀与环保》
CAS
CSCD
北大核心
2016年第4期33-35,共3页
Electroplating & Pollution Control
关键词
镁合金
磷酸盐
转化膜
耐蚀性
装饰性
magnesium alloy
phosphate
conversion film
corrosion resistance
decorative
