Austenite Grain Growth in Peritectic Solidified Carbon Steels Analyzed by Phase-Field Simulation

作者：Ohno Munekazu^*; Tsuchiya Shingo; Matsuura Kiyotaka

来源：Metallurgical and Materials Transactions A-Physical Metallurgy and Materials Science, 2012, 43A(6): 2031-2042.

DOI：10.1007/s11661-011-1072-6

The formation of coarse columnar grains (CCGs) in the as-cast austenite structure of peritectic carbon steels is a serious problem in continuous casting processes. Recently, it was elucidated that the formation of CCGs is ascribed to a discontinuous grain growth. Furthermore, the critical condition for the discontinuous growth to occur was elicited on the basis of phase-field simulations and a theory of grain growth. In this study, by means of the phase-field simulations, the detailed investigation is carried out for the grain coarsening of the as-cast austenite structure. It is demonstrated in the two-dimensional simulations that the coarsest grain structure emerges by the discontinuous growth in the vicinity of the critical condition. In addition, a model for predicting the upper limit of grain size during the discontinuous growth is proposed. The model successfully describes the experimental result with reasonable accuracy.

• 出版日期2012-6