Slip band formation at free surface of lath martensite in low carbon steel. (15th February 2019)

• Record Type: Journal Article
• Authors: Inoue, Junya; Sadeghi, Alireza; Koseki, Toshihiko
• Is Part Of: Acta materialia. Volume 165(2019)
• Page Start: 129
• Page End: 141
• Publication Date: 2019-02-15
• Subjects: Lath martensite -- Substructure sliding -- Retained austenite -- Non-Schmid effect; Materials -- Periodicals; Materials science -- Periodicals; Materials -- Mechanical properties -- Periodicals; Metallurgy -- Periodicals; Chemistry, Inorganic -- Periodicals; 620.112
• DOI: 10.1016/j.actamat.2018.11.026
• Languages: English
• ISSNs: 1359-6454

Abstract

Abstract: Cross-sectional observations of the deformation bands formed during in situ tensile observation at the free surface of both ultralow- and low-carbon lath martensitic steels were conducted. The cross-sectional observations clearly revealed the formation of steps along substructure boundaries of the ultralow-carbon lath martensite during deformation. In contrast, severe undulation indicating strain accumulation was observed in the vicinity of high-angle boundaries for the low-carbon lath martensite, and no clear steps were formed along substructure boundaries, even though small filmlike ferrites were found. The "greasy-film" mechanism proposed by Maresca [Maresca et al., Modelling and Simulation in Materials Science and Engineering 24(2016)025006, Maresca and Curtin, Acta Materialia 134(2017)302] as well as the plastic instability theory proposed by Dao and Asaro [Dao and Asaro: Mech. Mater., 23(1996)71] was examined considering the non-Schmid effects and the anisotropic activation of slip systems in lath martensite. Graphical abstract: Image 1