A novel multi-step intercritical heat treatment induces multi-phase microstructure with ultra-low yield ratio and high ductility in advanced high-strength steel. (October 2018)

• Record Type: Journal Article
• Authors: Xie, Z.J.; Han, G.; Zhou, W.H.; Wang, X.L.; Shang, C.J.; Misra, R.D.K.
• Is Part Of: Scripta materialia. Number 155(2018)
• Page Start: 164
• Page End: 168
• Publication Date: 2018-10
• Subjects: Interctitical heat treatment -- Deformation induced martensite transformation -- Retained austenite -- Low yield ratio; Materials -- Periodicals; Metallurgy -- Periodicals; Metalen; Legeringen; Materiaalkunde; Metals, metalworking and machinery industries; Metals; Electronic journals; 620.11
• DOI: 10.1016/j.scriptamat.2018.06.042
• Languages: English
• ISSNs: 1359-6462

Abstract

Abstract: A significant volume fraction of 26% retained austenite was obtained via a two-step intercritical treatment in a low carbon low alloy steel with ultra-high tensile strength of ~1200 MPa, ultra-low yield ratio of 0.32, excellent uniform elongation of ~16.4% and total elongation of ~23%. The ultra-low yield ratio and excellent uniform elongation implied high work hardening and excellent formability. The high work hardening and ultra-high tensile strength are attributed to deformation-induced twin-martensite. Graphical abstract: Unlabelled Image