Determination of microtexture of initial stages of secondary recrystallisation in Fe–3 wt-%Si by etch pitting

Abstract

Regular grain oriented silicon iron, produced by a two stage cold rolling technique, has been the subject of many investigations owing to its economic significance as sheet steel for transformer cores. In particular, many investigations of the texture development through the various processing stages have been carried out by calculation of the orientation distribution functions. The final processing stage is a high temperature box annealing, by which discontinuous grain growth (secondary recrystallisation), controlled by a fine dispersion of second phase particles, leads to a very sharp Goss texture. To investigate the conditions for secondary recrystallisation, material from two stages of processing has been examined: the primary recrystallised material and the material just before the start of secondary grain growth. Utilising the etch pit method – a well established and powerful technique for single orientation determination – in addition to grain size measurements, both applied to scanning electron micrographs, grain size and orientation distributions of Goss oriented and other matrix grams were measured and compared for the two types of material. The potential of this technique and the interpretation of the results m the context of the material used are discussed.

MST/1513