Synthesis of resource saving Fe-based semi-hard magnetic material by controlling of nano-crystal structure

2014 Fiscal Year Final Research Report

• Project/Area Number: 25600037
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Nanomaterials engineering
• Research Institution: Tohoku University
• Principal Investigator: MAKINO Akihiro 東北大学, 金属材料研究所, 教授 (30315642)
• Project Period (FY): 2013-04-01 – 2015-03-31
• Keywords: 金属物性 / 半硬質磁性 / 組織制御 / 粒成長

Outline of Final Research Achievements

Development and magnetic properties of an alloy that can change from very soft to semi-hard magnetic are reported. We found that as quenched ribbons of Fe75.3Pt8B12P4Cu0.7 alloy are amorphous by X-ray. Heat treatment in the temperature range of 400-450 ℃ causes formation of many a-Fe grains in the amorphous matrix. Hard magnetic L10 FePt grains appear at 520 ℃. This alloy shows a high saturation magnetic flux density [Bs >1.55 T] along with the ability to vary coercivity (Hc) from 25 A/m to 11000 A/m. The ability to control magnetic properties lies in a precise control over the soft and hard magnetic phases, which are strongly exchange coupled.

Free Research Field

ナノ材料工学