Orientation Selection Behavior During Secondary Recrystallization in Grain-Oriented Silicon Steel

The key index of grain-oriented silicon steel is the sharpness of secondary recrystallization Goss ({110}<001>) texture, which is determined by the matrix grain size distribution, texture environment and inhibitor level. In the widely used low-temperature slab heating process in virtue of high efficiency and low-cost manufacturing, the instability of inhibitor and the enlarged matrix grain size distribution seriously restrict the occurrence of secondary recrystallization and the sharpness of Goss texture. The investigation on orientation selection behavior during abnormal grain growth can explore the potential routines to solve the problem. In this work, the evolution process of secondary recrystallization texture in grain-oriented silicon steel has been studied by both experiment and calculation. It is found that single Goss texture is finally obtained by means of continuous orientation selection during secondary recrystallization. The kinetic model for secondary recrystallization, introduced with orientation-dependent relative grain boundary energy coefficient, can describe quantitatively the difference in growth rate between Goss grains with various deviation angles and non-Goss grains. The combined effects of grain size distribution, grain boundary characteristic between Goss and matrix grains, together with inhibition force level on orientation selection behavior are analyzed. Accordingly, a multi-parameter matching method for promoting the advantage of Goss grains in orientation selection is proposed.