Barium phosphate conversion coating on die-cast AZ91D magnesium alloy

被引：17
作者：
Liu Feng [1 ,2 ]
Shan Da-yong [1 ]
Han En-hou [1 ]
Liu Chang-sheng [2 ]
机构：
[1] Chinese Acad Sci, State Key Lab Corros & Protect, Inst Met Res, Shenyang 110016, Peoples R China
[2] Northeastern Univ, Sch Met & Mat, Shenyang 110016, Peoples R China
来源：
TRANSACTIONS OF NONFERROUS METALS SOCIETY OF CHINA | 2008年 / 18卷
关键词：
barium phosphate conversion coating; die-cast AZ91D magnesium alloy; micro-cracks; corrosion resistance;
D O I：
10.1016/S1003-6326(10)60229-4
中图分类号：
TF [冶金工业];
学科分类号：
0806 ;
摘要：
Poor corrosion resistance limits the application of magnesium alloys. Conversion coating is widely used to protect magnesium alloys because of easy operation and low cost. A novel conversion coating on die-cast AZ91D magnesium alloy containing barium salts was studied. The optimum concentrations of Ba(NO3)(2), Mn(NO3)(2) and NH4H2PO4 are 25 g/L, 15 mL/L and 20 g/L, respectively, based on orthogonal test results. The treating time, solution temperature and pH value are settled to be 5-30 min, 50-70 degrees C and 2.35-3.0, respectively. The corrosion resistance of barium conversion coating is better than that of manganese-based phosphate conversion coating by immersion test. The coating is composed of Ba, P, O, Mg, Zn, Mn and Al by EDX analysis.
引用
收藏
页码：S344 / S348
页数：5
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