Development of an industrial evaluation technique for vacancy behavior using muon spin relaxation method

2015 Fiscal Year Final Research Report

• Project/Area Number: 25289260
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 一般
• Research Field: Material processing/Microstructural control engineering
• Research Institution: University of Toyama
• Principal Investigator: Nishimura Katsuhiko 富山大学, 大学院理工学研究部(工学), 教授 (70218189)
• Co-Investigator(Kenkyū-buntansha): MATSUDA Kenji 富山大学, 大学院理工学研究部, 教授 (00209553)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: 金属生産工学 / アルミニウム合金 / 原子空孔 / ミュオン / スピン緩和 / クラスター / 電子密度計算

Outline of Final Research Achievements

Zero field muon spin relaxation experiments were carried out for Al-Mg-Si, Al-0.5%Mg and Al-0.5%Si alloys under various heat treatments, which have demonstrated that the muon trapping rates (νt) depended on the heat treatment on the sample and solute concentrations: (1) the concentration of dissolved Mg dominates the νt values at lower temperatures below 120 K; (2) the νt values around 200 K reflect a number of clusters; (3) the vacancy trapping is obvious around room temperature; (4) the natural aging effect is clearly observed with Al-0.5%Si. The isothermal time dependence of spin relaxation rates with the sample of Al-1.6%Mg2Si at 280, 290 and 300K showed that the spin relaxation rates at 280 K did not change for the first about 100 minutes after the solution heat treatment and quenching, then decreased with time in the logarithmic scale. Those at 290 and 300 K decreased with time from the beginning. Thus, muons clearly monitored kinetic behavior of vacancies.

Free Research Field

固体物性工学