Microstructure control by HPT deformation to improve strength and toughness of austenitic stainless steels

2014 Fiscal Year Final Research Report

• Project/Area Number: 24360306
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 一般
• Research Field: Material processing/treatments
• Research Institution: Toyohashi University of Technology
• Principal Investigator: UMEMOTO Minoru 豊橋技術科学大学, 国際教育センター, 特任教授 (90111921)
• Co-Investigator(Kenkyū-buntansha): TODAKA Yoshikazu 豊橋技術科学大学, 機械工学研究科, 准教授 (50345956)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: ステンレス鋼 / 巨大ひずみ / 強度 / 延性 / TRIP

Outline of Final Research Achievements

In the present study, strengthening and toughening of stainless steels was examined by applying HPT (High-Pressure Torsion) deformation. It was found that HPT deformation introduce strain induced transformation larger extent than conventional rolling. In specimens subjected HPT deformation, diffusion is enhanced and the precipitation of G-phase or s-phase were observed in the first time. In the later part of the present study, the high strength stainless steels prepared by HPT deformation was annealed to obtain c phase. It was found that such specimen showed good ductility due to the strain induced martensitic transformation. In summary, by optimizing the deformation and annealing conditions, it is possible to obtain high strength stainless steels with good ductility arising from TRIP phenomena.

Free Research Field

材料工学