镁合金表面铝合金化层组织及性能研究  

Research on microstructure and property of surface aluminum-alloying layer of magnesium alloy

作　　者：张雄[1] 董选普[1] 陈东风[1] 

机构地区：[1]华中科技大学材料成形与模具技术国家重点实验室,湖北武汉430074

出　　处：《功能材料》2011年第5期928-932,共5页Journal of Functional Materials

基　　金：国家自然科学基金资助项目(50775085)

摘　　要：使用消失模铸造方法在镁合金表面制备了一层铝合金化层,并对合金化层的金相组织、成分、相组成及腐蚀性能进行了分析。结果表明,当真空度为0.08MPa,铝粉粒度为150μm时,镁合金表面生成的铝合金化层厚度为750μm,新相覆盖率达到76.2%;合金化层呈菊花状或网状,与基体为冶金结合,其主要组成物相为Mg17Al12、Mg和Al;经表面合金化后的镁合金耐蚀性都有所提高,只有当新相覆盖率大于临界值37.1%时,镁合金表面铝合金化层才能起到防腐作用,且覆盖率越高抗蚀性越好。An aluminum-alloying layer was fabricated on magnesium alloy surface by the method of lost foam casting.And microstructure,composition,phase and corrosion property of the surface alloying layer were also analyzed.The results show that the thickness of the layer is 750μm and coverage of the new phase reaches to 76.2% when the vacuum degree was 0.08MPa and the particle size of Al powder was 150μm.The main phase of the surface alloying layer which shows chrysanthemum or mesh structure and is metallurgical bonded with the substrate is Mg17Al12,Mg and Al.The corrosion property of surface alloyed magnesium alloy is improved.Only when the coverage of the new phase is greater than the critical value of 37.1%,the surface alloying layer can play a role in anti-corrosion and the higher the coverage is,the better the corrosion resistance will be.

关 键 词：镁合金 表面合金化 耐蚀性 消失模铸造 

分 类 号：TB331[一般工业技术—材料科学与工程]