Influence of electromagnetic stirring on microstructure of AZ91-0.8%Ce magnesium alloy
来源期刊：中南大学学报(英文版)2006年第6期
论文作者：刘生发 康柳根 韩辉 刘林艳 邹晓强 郭洪河
文章页码：613 - 617
Key words：AZ91 magnesium alloy ; electromagnetic stirring ;cerium;microstructure refinement
Abstract: Effect of electromagnetic stirring on microstructure of AZ91-0.8%Ce magnesium alloy was investigated.The results show that electromagnetic stirring causes a change of morphology ofα-Mg phase from coarse dendrites to fine rosette-like or spherical shape.Grain size is significantly refined within the range of input voltage 75?125 V,moreover,the optimum input voltage corresponded to the minimum value(64μm)of grain size is 125 V.Compared to the non-stirred condition,the amount of β-Mg17Al12 precipitate under the stirred condition obviously increases.The grain refinement of AZ91-0.8%Ce alloy is mainly attributed to multiplication of existing grains in the melt caused by forced fluid flow under electromagnetic stirring condition. Addition of 0.8%Ce results in the formation of‘necking’at secondary dendrite arm roots ofα-Mg crystals,and consequently,it is helpful to increase the number of heterogeneous nucleation.
