Temperature dependence of strengthening mechanisms in a twinning-induced plasticity steel. (May 2019)

• Record Type: Journal Article
• Authors: Liang, Z.Y.; Luo, Z.C.; Huang, M.X.
• Is Part Of: International journal of plasticity. Volume 116(2019:May)
• Page Start: 192
• Page End: 202
• Publication Date: 2019-05
• Subjects: TWIP steel -- Strengthening mechanism -- Dislocation -- Twinning; Plasticity -- Periodicals; Plasticité -- Périodiques; Plasticity; Periodicals; 620.11233
• DOI: 10.1016/j.ijplas.2019.01.003
• Languages: English
• ISSNs: 0749-6419

Abstract

Abstract: The temperature dependence of strengthening mechanisms in twinning-induced plasticity (TWIP) steels is of fundamental importance because of the broad range of environmental temperatures during manufacturing and applications. In this study, the temperature dependence of dislocation, twin and dynamic strain aging strengthenings, was investigated over a wide range of temperatures ranging from 298 to 973 K. Uniaxial tensile tests and microstructural characterization via electron backscatter diffraction and electron channelling contrast imaging were carried out. In addition, synchrotron X-ray diffraction was used to measure the dislocation density at various temperatures. Based on the experimental observations, the strengthening mechanisms at various temperatures are elucidated with the quantification of the respective strengthening contributions from dislocations, twins and dynamic strain aging. These experimental results shed light on the temperature-dependent plasticity of TWIP steels and provide guidance for developing temperature-sensitive constitutive models. Graphical abstract: Image 1 The active strengthening mechanisms at various temperatures (DT-deformation twinning, FH-forest hardening and DSA-dynamic strain aging). Highlights: The strengthening mechanisms of the TWIP steel depend strongly on temperature. DSA occurs from 373 to 673 K with a maximum strength contribution of ∼200 MPa. Twinning is active from 298 to 473 K, yet insignificant to the strain hardening. Strain hardening is dominated by dislocation multiplication from 298 to 973 K.