Dynamic observation of bainite transformation in a Fe-C-Mn-Si superbainite steel

Abstract

The dynamic observations of bainitic transformation in a Fe-C-Mn-Si superbainite steel were conducted on a high temperature laser scanning confocal microscope. It is indicated that the mutual intersection of bainite sheaves often occurs during growth of bainite ferrite, resulting in an interlocked bainite microstructure. Moreover, bainite transformation is promoted by higher austenization temperature and the longer and finer bainite platelets are obtained. Further, The average growth rate of bainite after austenization at 1 100 ° is calculated as 5.8 µm·s⁻¹. In situ observation investigation makes it possible to identify bainite transformation in real time during isothermal holding.

Keywords

bainite transformation / dynamic observation / microstructure / growth rate

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