Budget Amount *help |
¥3,400,000 (Direct Cost: ¥3,400,000)
Fiscal Year 1999: ¥1,400,000 (Direct Cost: ¥1,400,000)
Fiscal Year 1998: ¥2,000,000 (Direct Cost: ¥2,000,000)
|
Research Abstract |
The giant magnetostrictive alloys newly developed have the brittleness peculiar to intermetallics, unfavorable for actuator's application. Here the giant magnetostrictive alloy, if combined with ductile and less magnetostrictive one by means of powder metallurgy, my possible be widely used as a functionally graded magnetostrictor of deflection-endurable type. The experimental results obtained on this idea are summarized as follows: 1. Tb,Dy,Fe elemental powders were able to be mechanically alloyed in non-oxygen atmosphere by ball milling and then, solidified into giant magnetostrictive alloy(Tb,Dy)Fe using spark plasma sintering system. 2. An optical magnetostrictive meter was newly designed and made up for the both measurement of linear and deflective displacements in applied field(H), where the latter's accuracy was 10ィイD1-4ィエD1rad under applied field〜110kA/m. 3. For typical giant magnetostrictive ally6s(TbxDy1-x)Fey, the effect of chemical composition, powder morphology,SPS pressure/sintering conditions on magnetostrictionλ-H curves, λ/ΔH was surveyed and finally, optimized. 4. It was numerically confirmed that giant/less magnetostrictive duplex alloys deflected at right angles to applied field, together with the relationship between microscopic morphology in the interface and it's fabrication parameters. 5. For a giant/zero magnetostrictive duplex alloy, as Fe-6.5Si,deflection Δθchanged linearly with applied field(Δθ/ΔH=1.1×10ィイD1-4ィエD1rad/kAmィイD1-1ィエD1),while large ductility for lower Si region and large deflection for higher Si region are evidently expected. Consequently, the functionally graded magnetostrictor turned out to be favorable for usage of contactless magnetic actuator(sensor).
|