Tohoku University · Engineering
Professor Kyosuke Yoshimi's research lab specializes in the development and characterization of advanced intermetallic and refractory metal-based materials for ultra-high temperature applications. The lab focuses on understanding defect structures, such as planar faults and vacancy dynamics, in Fe-Al and Mo-Si-B systems, using advanced electron microscopy and thermomechanical processing. A key research direction involves designing pseudo in situ composites through spark plasma sintering to achieve high-density, multi-phase materials with enhanced thermal and mechanical stability. The lab also investigates phase stability, precipitation behavior, and mechanical properties under extreme conditions, aiming to enable next-generation materials for aerospace and energy systems.
Figures are computed from collected data and may differ slightly.
Abstract Thermally introduced planar faults are investigated both in an Fe-35 mol.%Al binary alloy and in B, Cr, Pd and W added ternary alloys using transmission electron microscopy. Air cooling of the alloys from 1273 K followed by annealing at 698 K for 120 h introduces two types of planar faults. One type is the antiphase boundary (APB), which is observed in all of the alloys. The other is the complex planar fault having both APB and stacking fault characters, which is observed in only the B-
Polycrystalline B2 FeAl sheets containing 40 and 46 mol% aluminum were prepared by arc-melting and hot-rolling. After annealing at 1123 K, they were cooled to room temperature at three cooling rates; i.e. i) air-cooling (about 25 K·s−1), ii) 0.065 K·s−1 and iii) 0.01 K·s−1. Hardness values are localized around the average value except Fe-46 mol%Al cooled at 0.065 K·s−1. Hardness of the air-cooled samples is much higher than that of slowly cooled samples at 0.01 K·s−1 because of the introduction
Open papers in the app to read, cite, and organize with AI.
