【摘要】 镁合金压铸件上涂覆有机涂层后的耐蚀性能与其涂装前的表面处理状态有着密切关系。采用中性盐雾试验和盐水浸渍法对经喷砂、打磨、无铬化学转化、微弧氧化4种不同表面预处理后的丙烯酸树脂涂层进行了耐蚀性测试。结果表明:采用合适的预处理能显著提高涂层的耐蚀性能,其中微弧氧化涂层耐蚀性最佳,在盐雾和盐水浸渍试验中失效时间分别达96h和168h;预处理后基材表面光滑的涂层失效形式以起泡为主,而具有微孔或粗糙表面的涂层则以点蚀为主。更多还原

【Abstract】 The corrosion resistance of acrylic resin coatings on the surface of Mg alloys subjected to different pretreatments was evaluated by neutral salt spray tests and solution immersion tests. It was found that the corrosion resistance of the organic coatings could be improved significantly by adopting proper pretreatment of Mg alloy. The micro-arc oxidized coating showed the best corrosion resistance, with endurance to salt spray and solution immersion of 96 h and 168 h respectively. Besides, the coatings on smooth pretreated Mg failed mainly due to bubbling, while those on pretreated Mg with microporous or rough surfaces failed mainly due to pitting.更多还原