EBSD study of a hot deformed austenitic stainless steel

• Published in: Materials science & engineering. A, Structural materials : properties, microstructure and processing Vol. 538; pp. 236 - 245
• Main Authors: Mirzadeh, H., Cabrera, J.M., Najafizadeh, A., Calvillo, P.R.
• Format: Journal Article Publication
• Language: English
• Published: Kidlington Elsevier B.V 15.03.2012; Elsevier
• Subjects: Acer inoxidable; Annealing; Applied sciences; Cold working, work hardening; annealing, quenching, tempering, recovery, and recrystallization; textures; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Dynamic recrystallization; Electron back-scattered diffraction; Enginyeria dels materials; Equations of state, phase equilibria, and phase transitions; Exact sciences and technology; General studies of phase transitions; Grain average misorientation; Heat treatment; Hot working; Hot working Electron back-scattered diffraction JMAK analysis Dynamic recrystallization Sigma3 annealing twin boundary Grain average misorientation; JMAK analysis; Materials science; Metals. Metallurgy; Methods of crystal growth; physics of crystal growth; Nucleation; Physics; Production techniques; Stainless steel; Theory and models of crystal growth; physics of crystal growth, crystal morphology and orientation; Treatment of materials and its effects on microstructure and properties; Àrees temàtiques de la UPC; Σ3 annealing twin boundary; Electron back-scattered diffraction; Hot working; Dynamic recrystallization; Grain average misorientation; JMAK analysis; Σ3 annealing twin boundary; Hot deformation; Grain size; Coincidence site lattice; Austenitic stainless steel; Crystal twin; Crystal defects; Annealing; Nucleation; Dynamical recrystallization; Stress-strain relations; EBSD; Twin boundaries; High angle boundary; Imaging; Growth mechanism; High frequency; Microstructure; Grain refinement
• ISSN: 0921-5093; 1873-4936
• DOI: 10.1016/j.msea.2012.01.037

► Microstructural characterization of an austenitic stainless steel by EBSD. ► The role of twins in the nucleation and growth of dynamic recrystallization. ► Grain refinement through the discontinuous dynamic recrystallization. ► Determination of recrystallized fraction using the grain average misorientation. ► Relationship between recrystallization and the frequency of high angle boundaries. The microstructural evolution of a 304 H austenitic stainless steel subjected to hot compression was studied by the electron backscattered diffraction (EBSD) technique. Detailed data about the boundaries, coincidence site lattice (CSL) relationships and grain size were acquired from the orientation imaging microscopy (OIM) maps. It was found that twins play an important role in the nucleation and growth of dynamic recrystallization (DRX) during hot deformation. Moreover, the conventional discontinuous DRX (DDRX) was found to be in charge of grain refinement reached under the testing conditions studied. Furthermore, the recrystallized fraction (X) was determined from the grain average misorientation (GAM) distribution based on the threshold value of 1.55°. The frequency of high angle boundaries showed a direct relationship with X. A time exponent of 1.11 was determined from Avrami analysis, which was related to the observed single-peak behavior in the stress–strain flow curves.