摘要
The optical microscope, SEM and EDS were adopted to analyze the rheoforming solidification morpholo-gies and microstructures of deformed AZ91D magnesium alloy after isothermal treatment in semisolid state. The re-sults show that primary α phase can be formed through attachment growth, when the liquid fraction is small; and primary α phase will grow in dendrites, when the liquid fraction is high. Eutectic solidification is carried out in the ways of both dissociated growth and symbiotic growth, de-pending on the morphology of primary α phase. Liquid with eutectic concentration solidifies into lamina eutectic. During solidification of the liquid pools inside grains, α phase can be formed through attachment growth. The eutectic solidifica-tion was mainly carried out in the dissociated pattern.
The optical microscope, SEM and EDS were adopted to analyze the rheoforming solidification morphologies and microstructures of deformed AZ91D magnesium alloy after isothermal treatment in semisolid state. The results show that primary α phase can be formed through attachment growth, when the liquid fraction is small; and primary α phase will grow in dendrites, when the liquid fraction is high. Eutectic solidification is carried out in the ways of both dissociated growth and symbiotic growth, depending on the morphology of primary α phase. Liquid with eutectic concentration solidifies into lamina eutectic. During solidification of the liquid pools inside grains, α phase can be formed through attachment growth. The eutectic solidification was mainly carried out in the dissociated pattern.
基金
This work was supported by the Industrial Breed of Shaanxi Provincial Education Committee(Grant Nos.02JC33).
关键词
镁合金
凝固模式
微观结构
等温线
半固体
magnesium alloy, semisolid, rheoforming solidified microstructure, quenching microstructure, solidification pattern.
