SUPERMAGNETOSTRICTIVE MATERIAL, ITS MANUFACTURING METHOD AND MAGNETOSTRICTIVE ACTUATOR AND MAGNETOSTRICTIVE SENSOR USING THE MATERIAL

摘要

PROBLEM TO BE SOLVED: To effectively increase Curie temperature with superior reproducibility by enabling positive and effective containment of hydrogen to rare earth- transition metal based supermagnetostrictive alloy. SOLUTION: Supermagnetostrictive material is composed of alloy whose main component is rare earth element and transition metal element. Hydrogen in a range of 0.01-1.5 wt.% is contained in the rare earth-transition metal alloy. Hydrogen is mainly added to an interstitial alloy, and content of hydride substance contained in the alloy is set to be less than 10 vol.%. When hydrogen adding treatment is performed, the alloy is thermally treated at a temperature in a range of 150-600 deg.C in an atmosphere containing hydrogen especially.