Tb-Dy-Fe

Tb-Dy-Fe twin crystal or polycrystal magnetostrictive materials are normally employed as driving unit in magnetostrictive actuator, yet the crystal boundary and twin crystal structure in the Tb-Dy-Fe materials hinder the movement of domain walls so that the displacement output under low magnetic field is rather small.

磁致伸缩型微位移致动器通常采用多晶或孪晶结构材料作为驱动单元，由于晶界和孪晶界对畴壁的移动具有阻碍作用，其低场下的位移输出较小，调控精度受到较大影响。

The directionally solidified Tb-Dy-Fe magnetostrictive alloys with < 110> orientation were prepared in a velocity range from 30 to 720 mm/ h, and the solidified morphologies change from planar, cellular to dendritic with increasing growth velocity.

采用区熔定向凝固方法，在30-720mm/h生长速度范围内，均能获得（110）轴向择优取向生长的Tb-Dy-Fe合金；凝固形态随生长速度提高出现从平面晶到胞状晶、树枝晶转变；

The Tb-Dy-Fe giant magnetostrictive material, a new type of magneto ( electro)-mechanical energy conversion material with large magnetostriction and rapid response, is a perfect element for micro-displacement actuator.

磁致伸缩是一种磁&机械耦合现象，以Tb-Dy-Fe为代表的稀土超磁致伸缩材料，其伸缩量为普通压电陶瓷的30-50倍，响应时间低于10.6秒，是理想的位移致动材料。