Revealing the Unexpected Two Variant Pairing Shifts Due to Temperature Change in a Single Bainitic Medium Carbon Steel

Abstract The microstructure of a low alloy medium carbon bainitic steel, austempered in the temperature range 275 °C to 450 has been investigated by detailed electron backscatter diffraction and variant pairing analysis. It is observed that tendency two distinct changes with varying temperature. At V1-V6 most frequent, whereas V1-V2 frequent at intermediate highest temperature, V1-V4 dominates. This from literature on steel where only dominant variants pairs, related common distinction bainite into lower upper bainite, are typically reported. change also many similarities martensite when its content changes. Another observation morphological orientation cementite strong relation austempering temperatures.