Suppressed deformation instability in the twinning-induced plasticity steel-cored three-layer steel sheet. (1st April 2018)

• Record Type: Journal Article
• Authors: Kim, Jung Gi; Baek, Seung Mi; Lee, Hak Hyeon; Chin, Kwang-Geun; Lee, Sunghak; Kim, Hyoung Seop
• Is Part Of: Acta materialia. Volume 147(2018)
• Page Start: 304
• Page End: 312
• Publication Date: 2018-04-01
• Subjects: TWIP steel -- Architectured materials -- Serration -- Yield point phenomena -- Interface; Materials -- Periodicals; Materials science -- Periodicals; Materials -- Mechanical properties -- Periodicals; Metallurgy -- Periodicals; Chemistry, Inorganic -- Periodicals; 620.112
• DOI: 10.1016/j.actamat.2018.01.042
• Languages: English
• ISSNs: 1359-6454

Abstract

Abstract: Deformation instabilities (i.e., yield point phenomenon (YPP) and serrated flow) were investigated for twinning-induced plasticity (TWIP) steel-core with low-carbon (LC) steel outer layer sheets. During tensile tests, both the YPP and serrated flow were suppressed as the volume fraction of the TWIP steel-core decreased. Electron backscattering diffraction analysis indicated that a strain gradient was induced, and that geometrically necessary dislocations (GNDs) accumulated at the TWIP-LC steel interface. With increase in the dislocation density by plastic deformation, the deformation instabilities in the TWIP-cored layer steel sheets were suppressed due to the reduced probability of interaction of dislocation with carbon-solutes. This result indicates that the strain gradient at the interface of the layered sheets not only enhances the mechanical property, but also suppresses deformation instability. Graphical abstract: Image 1