Fabction of novel iron core materials by control of nano-scale precipitaion and texture

2018 Fiscal Year Final Research Report

• Project/Area Number: 16K14430
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Material processing/Microstructural control engineering
• Research Institution: Tohoku University
• Principal Investigator: Suzuki Shigeru 東北大学, 多元物質科学研究所, 教授 (40143028)
• Co-Investigator(Kenkyū-buntansha): 佐藤 成男 茨城大学, 理工学研究科(工学野), 教授 (40509056) ; 小貫 祐介 茨城大学, フロンティア応用原子科学研究センター, 産学官連携助教 (50746998) ; 藤枝 俊 大阪大学, 工学研究科, 准教授 (60551893)
• Project Period (FY): 2016-04-01 – 2019-03-31
• Keywords: 電磁ステンレス鋼 / 析出 / 集合組織

Outline of Final Research Achievements

The effect of alloying elements Ni and Al on the mechanical properties of precipitation-hardened soft-magnetic stainless steels was investigated. Thermodynamic calculations suggested that the aging treatments led to precipitation of NiAl compounds with B2 structure and Fe2Mo-type Laves phases. By changing the concentration of the alloying elements, the B2-type NiAl precipitates were mainly responsible for the precipitation hardening, and the Vickers hardness was hardly affected by the Mo content. Small-angle X-ray scattering analysis was used to determine the size and number density of the fine precipitates, which contributed to the hardening. The high-density NiAl precipitates grew to a few nanometers in radius after an adequate period of aging. It was indicated that grains with the <100> texture component preferentially evolve during compressive deformation under low strain rates at higher temperatures. The optimum conditions for the <100> texture evolution are proposed.

Free Research Field

材料工学

Academic Significance and Societal Importance of the Research Achievements

電磁ステンレス鋼には、耐食性以外に、高い強度や軟磁性特性が求められる。そうした複合的特性を学術的に取り組んだ研究は少なかった。本研究では、それらの特性を向上させるために、合金の化学組成やプロセスは、実験室レベルで研究を行ってきた。こちらの知見は、工業的な実際のアクチュエータ等の製造でも活用される可能性があり、社会的な意義も大きい。