About this Abstract |
Meeting |
2022 TMS Annual Meeting & Exhibition
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Symposium
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Ultrafine-grained and Heterostructured Materials (UFGH XII)
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Presentation Title |
Micro-macro Synergy Effects in Harmonic Structure Steels Design |
Author(s) |
Kei Ameyama |
On-Site Speaker (Planned) |
Kei Ameyama |
Abstract Scope |
Harmonic Structure (HS) design was applied to low carbon, medium carbon and stainless steels. The HS is a heterogeneous microstructure with a spatial distribution of ultra-fine grains (UFG) and coarse grains (CG), that is, the CG areas (‘Core’) embedded in the matrix of three-dimensionally continuously connected network of UFG areas (‘Shell’). The HS materials demonstrate unique deformation behaviors which were attributed to the micro-macro synergy effects. A low carbon HS steel demonstrated an avalanche discontinuous yielding, and an SUS316L HS stainless steel showed preferential recrystallization in the Shell by thermo-mechanical treatments. These unique behaviors are because of the stress concentration to the UFG-Shell network structure, which also accelerates the strain hardening of HS materials to increase the strength as well as ductility. Additionally, a medium carbon steel was found that carbon content heterogeneity during HS fabrication process resulted in an unusual microstructure with a superior strength / tensile toughness balance. |
Proceedings Inclusion? |
Planned: |
Keywords |
Iron and Steel, Mechanical Properties, Phase Transformations |