电磁分离制备过共晶Al-5%Fe自生表层复合材料

Hypereutectic Al-5%Fe in-situ surface layer composite produced by electromagnetic separation

利用电磁分离工艺成功地制备了Al-5%Fe过共晶合金自生表层复合材料,通过改变磁场作用时间来控制富铁相的迁移,以使其更好地沿径向分布。研究了Mn对富铁相形态改变的影响,实验表明在Mn/Fe的摩尔比为1．4～1．5时,针状的富铁相变成了块状或汉字状,使之更容易在熔体中迁移。并测试试样硬度和铁含量的分布,结果表明:试样的心部富铁相含量大大降低,组织大部分是共晶组织,表层区富集了大量的富铁相,并且硬度要明显高于心部,二者之间形成很好的过渡层,使增强相和基体得到更好的结合。

Hypereutectic Al-5 % Fe in-situ surface layer composite was produced successfully by electromagnetic separation process. In order to control migration of iron-rich phase and make it distribute well along the radial direction,different imposing time of high frequency magnetic field is used. And the effect of Mn on the shape of iron-rich phase has been studied. It is found that the n（Mn） ; n（Fe） is 1.4 to 1.5 can get the best effect. The shape of iron-rich phase has been changed into spherical, which makes it migrate in melt easily. In this paper, sample hardness （HV） and distribution of Fe are tested. The results show that the center of sample mainly consists of eutectic structure,while the surface layer is rich in iron-rich phase. And the hardness is higher than the center obviously,a transitional layer formed between the center area and the surface layer,make the reinforced phase and matrix jointed firmly.