基于液/半固态铸造复合的5083/AZ31B层状复合材料界面研究

Study on the Interface of Layered Composites 5083/AZ31B Based on Liquid-semisolid Casting

针对单一镁合金耐蚀性差的问题,采用液/半固态铸造复合法制备了5083/AZ31B层状复合材料。借助金相显微镜以及X射线衍射对层状材料复合界面显微组织和相组成进行了分析。利用显微硬度仪对复合界面区域进行显微硬度测试。结果表明:液/半固态铸造法制备的5083/AZ31B复层材料获得了良好的冶金结合;层状复合材料分为3个明显区域:镁合金基体、铝合金基体和宽度约为38μm的中间元素扩散区;中间元素扩散区以Mg17Al12和Mg2Al13等金属间化合物为主,其显微硬度明显高于两侧基体的硬度。

Considering the poor corrosion resistance of single magnesium alloy,5083/AZ31B layered composite was prepared by liquid/semisolid casting method.The microstructure and phase composition of layered composite interface were analyzed by means of metallographic microscope and X-ray diffraction.The microhardness of composite interface area was tested by microhardness tester.The results showed that the 5083/AZ31B layered material prepared by liquid/semisolid casting method obtained good metallurgical bonding.Layered composites are divided into three distinct zones:magnesium alloy matrix,aluminum alloy matrix and intermediate element diffusion zone with width of about 38 μm.Intermetallic compounds,such as Mg_(17)Al_(12) and Mg_2 Al_3,dominated the diffusion zone of intermediate elements,and their microhardness was significantly higher than that of the matrix on both sides.