Study of the recrystallization kinetics in Fe3%Si steels (COG process) during the 1st recrystallization using GOS (EBSD).

F. CRUZ-GANDARILLA; H.F. MENDOZA-LEON; R.E. BOLMARO; A.M. SALCEDO-GARRIDO; J.G. CABAÑAS-MORENO; AVALOS, M.

Saint George

Conferencia; 18th International Conference on Textures of Materials; 2017

Brigham Young University, Utah.

Fe3%Si alloys with Goss texture are essential in the manufacture of electrical transformers. Obtaining these materials requires several different sub-processing stages, like the one called primary recrystallization, fundamental key process preceding abnormal grain growth. The structure of grains and the different microstructural aspects of this stage will determine the conditions for developing the Goss orientation during abnormal grain growth [1].The kinetics of recrystallization have been characterized by studying properties, dependent on recrystallized volume, like hardness, volumes of texture components, etc. The evolution of the recrystallized volume has been modeled following Johnson-Mehl-Avrami-Kolmogorov (JMAK) formalism [2]. Recrystallized and non-recrystallized grains are not uniquely characterized by these global methods and a more local characterization is needed.Recovery and recrystallization happening during heat treatments involve changes in dislocation densities and their characteristic arrangements, what are reflected in the misorientations. Grain Orientation Spread (GOS), Grain Average Misorientation (GAM), Kernel Average Misorientation (KAM), etc. are useful parameters calculated from EBSD data to study these variations [3].The purpose of this work was to use those magnitudes (GOS, GAM and KAM) calculated from several EBSD scans, performed at increasing heat treatment times, to characterize the kinetics of the 1st recrystallization in an Fe3%Si alloy. Hardness measurements were made simultaneously in order to validate the evolution of the recrystallization by classical ways. It was found that the global GOS (including grains of all orientations) shows a behavior similar to hardness. When grains belonging to separate texture components are analyzed, gamma grains are the first ones to recrystallize and alfa component the last. A further study is necessary to determine limits for those parameters below which grains can be considered recrystallized. The experiments suggest so far that there are not unique values for all texture components.[1] F. Cruz-Gandarilla, R. Penelle, T. Baudin, H.F. Mendoza León and J. G. Cabañas-Moreno. (2008) Proceedings of the 15th ICOTOM. Ceramic Transactions, Volume 200. 123, Ed. WILEY.[2] F.J. Humpheyrs and M. Hatherly. RECRYSTALLIZATION AND RELATED ANNEALING PHENOMENA. (2004) 2dn Ed. ELSEVIER. ISBN: 0 08 044164 5 [3] F. Cruz-Gandarilla, A.M. Salcedo-Garrido, R.E. Bolmaro, T. Baudin, N.S. De Vincentis, M. Avalos, José G. Cabañas-Moreno, H.F. Mendoza-León. (2016) Materials Characterization 118, 332.