Crystal growth of high performance giant magnetostriction alloys by using micro-pulling down method

2014 Fiscal Year Final Research Report

• Project/Area Number: 24560905
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Metal making engineering
• Research Institution: Tohoku University
• Principal Investigator: OIKAWA Katsunari 東北大学, 工学(系)研究科(研究院), 教授 (70356608)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: 超磁歪 / 単結晶 / ミクロ組織 / 偏析

Outline of Final Research Achievements

Fe2(Dy0.73Tb0.27) alloys have been received great attention as vibration-powered generator materials. In this study, the fiber shape single crystals of Fe2(Dy0.73Tb0.27) alloys were prepared by the micro-pulling-down method. Optimum conditions for the crystal growth, the solidification behavior and physical properties of them were investigated. As the results, the single crystal wires approximately 2 mm in diameter could be grown by 30mm/h pulling-down-rate using CaO crucible under Ar+6%H2 atomspherre. The effective distribution coefficient of them approximately is unit, suggesting that the macroscopic segregation is very small. The saturation magnetostriction increases with increasing the annealing temperature although the crystals annealed higher than 1173 K were broken. In addition, Zr additions increase the saturation magnetization. The sample annealed at 1173 K showed the maximum saturation magnetization about 1900ppm.

Free Research Field

金属材料学