Terfenol-D 棒磁致伸缩特性及可加工性能研究

摘要

The non-linear relationship between the magnetostrictive strain and magnetic field intensity will affect the precision and stability of the actuator.This paper tries to reduce the eddy current loss in the Terfenol-D rod to improve linearity by machining radial grooves in the surface of the rod.The Terfenol-D rod was extremely difficulty to machine because of its brittleness.Wire-electrode cutting and precision grinding were preliminary chosen for the slotting,and the experimental results show that although the flake pits will be produced in the machining surface of wire-electrode cutting,the magnetostrictive property of Terfenol-D rod slotted was less af-fected comparing with precision grinding.The tests of the magnetostrictive strain in the Terfenol-D rod show that the eddy current loss was reduced and the linearity of output displacement was significantly improved by slotting 4 radial grooves in the rod surface.%Terfenol-D 中磁致伸缩应变与磁场强度关系的非线性,影响了磁致伸缩控制元件的精度和稳定性.拟采用轴向开槽的方式降低 Terfenol-D 棒由于涡流损耗产生的热致变形.但是由于材料本身的物理特性,Terfenol-D 棒体加工难度很大.为对 Terfenol-D 材料的加工性能进行研究,选用了线切割和精密磨削两种方式对 Terfenol-D 棒进行开槽处理,结果表明线切割后加工表面虽然有一定的剥落凹坑产生,但对棒体的磁致伸缩特性影响较小.Terfenol-D 棒开槽前后伸缩量测试结果表明在棒体表面开4轴向槽可以降低材料的涡流损耗,提高输出位移-磁场强度关系的线性度.