Irradiation damage in refractory high entropy alloys focusing on the recovery of the lattice defect

2017 Fiscal Year Final Research Report

• Project/Area Number: 15K06484
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Structural/Functional materials
• Research Institution: Osaka University
• Principal Investigator: Takeshi Nagase 大阪大学, 超高圧電子顕微鏡センター, 准教授 (50362661)
• Co-Investigator(Kenkyū-buntansha): 西 竜治 大阪大学, 超高圧電子顕微鏡センター, 准教授 (40243183)
• Project Period (FY): 2015-04-01 – 2018-03-31
• Keywords: ハイエントロピー合金 / 照射損傷 / 原子力材料 / 超高圧電子顕微鏡法

Outline of Final Research Achievements

The phase stability of high entropy alloy (HEA) was investigated by High Voltage Electron Microscopy (HVEM) focusing on the occurence of solid state amorphization(SSA). The occurence of SSA was not detected under fast electron irradiation in equiatomic TiNbTaZr with BCC structure, equiatomic TiNbTaZrV with BCC structure and CoCrCuFeNi with FCC structure, and non-equiatomic Al0.3CoCrFeNi with BCC structure. In contrast, non-equiatomic Al0.5TiZrPdCuNi with BCC structure shows the SSA regardless of the initial microstructure (i.e., "coarse crystalline structure" or "nano-crystalline structure with grain boundaries as a sink for point defects"). This result suggests that the Al0.5TiZrPdCuNi HEA from other common alloys and the other HEAs. The SSA behavior in Al0.5TiZrPdCuNi HEA investigated by HVEM indicated that SSA behavior in Al0.5TiZrPdCuNi HEA was similar to that in intermetallic compounds reported to date.

Free Research Field

構造・機能材料