Development of heat-resistant ferrous alloys based on new precipitation hardening mechanism

2016 Fiscal Year Final Research Report

• Project/Area Number: 26289259
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 一般
• Research Field: Structural/Functional materials
• Research Institution: Osaka University
• Principal Investigator: Yasuda Hiroyuki 大阪大学, 工学(系)研究科(研究院), 教授 (60294021)
• Project Period (FY): 2014-04-01 – 2017-03-31
• Keywords: 構造・機能材料 / 格子欠陥 / 転位 / 析出強化 / 耐熱合金

Outline of Final Research Achievements

In the present study, we succeeded in developing high temperature structural materials composed of (bcc+L21) phases. The L21 phase is precipitated in the bcc matrix in Fe-Al-Ni and Fe-Al-Co single crystals doped with a small amount of Ti and V. The (bcc+L21) alloys show higher strength than ferritic heat-resistant steels. Moreover, <001> dislocations which hardly move in bcc metals can be observed in V-doped crystals. So, the behavior of <001> dislocations in the (bcc+L21) single crystals can be examined. In addition, co-doping of Ti and V leads to a decrease in the misfit strain, which results in high strength at high temperatures.

Free Research Field

材料強度学