镁合金磷酸盐、锡酸盐化学转化工艺及膜层耐蚀性研究  

Technology for Preparation of Chemical Conversion Coating on Magnesium Alloys from Phosphate/Stannate Solutions and Corrosion Resistance of the Coating

作　　者：陈祥[1,2] 金华兰[3] 杨湘杰[1] 叶寒[1] 吴丹[1] 王明[1] 

机构地区：[1]南昌大学机电工程学院,江西南昌330031 [2]宁波大红鹰职业技术学院,浙江宁波315175 [3]南昌大学材料科学与工程学院,江西南昌330031

出　　处：《材料保护》2008年第8期22-24,共3页Materials Protection

摘　　要：为研究压铸AZ91D镁合金和挤压态AZ31B、AZ61镁合金磷酸盐、锡酸盐化学改性的表面处理工艺及转化膜性能,采用扫描电镜(SEM)、X射线衍射(XRD)、盐雾试验等方法,分析了膜层厚度、表面形貌和相结构,并与不同处理工艺的试验结果进行了对比。结果表明,磷酸盐转化膜较为均匀平整,膜层较厚,存在一些显微裂纹。锡酸盐化学转化膜为近球形微型颗粒密积而成,颗粒之间存在缝隙,微观上凹凸不平,相组成主要为Mg、A l12Mg17和MgSnO3.3H2O,呈晶态结构。两种膜层都可以大大提高镁合金基体的耐腐蚀性能。A new chemical surface-modification technology for die-casting AZ91D and extruded AZ31B magnesium alloys in phosphate/stannate chemical conversion solutions was investigated.The thickness,morphology,and phase composition of the chemical conversion coating were analyzed by means of scanning electron microscopy,X-ray diffraction,and salt-spray test.Operation conditions of phosphate/stannate treatment for magnesium alloys are discussed.Results showed that the phosphate conversion coating was uniform,smooth,and thick,and it contained some micro-cracks.The stannate conversion coating,containing nearly-spherical tiny particles of magnesium stannate,was mainly composed of Mg,Al12Mg17,and MgSnO3·3H2O,and there were interspaces between these tiny particles.

关 键 词：镁合金 化学转化膜 磷酸盐 锡酸盐 耐蚀性能 

分 类 号：TG174.44[金属学及工艺—金属表面处理]