EFFECTS OF HOLDING TEMPERATURE ON BAINITE TRANSFORMATION IN CR-MO STEEL
DOI:
https://doi.org/10.15282/jmes.7.2014.9.0107Keywords:
Variant analysis; bainite; phase transformation; heat affected zone (HAZ); EBSDAbstract
The effect of holding temperature on the variant selection mechanism during bainite transformation was investigated in 2Cr-1Mo steel. The transformation behaviour was studied by using high temperature laser scanning confocal microscopy (LSCM) via in situ observation. The specimen was heat treated to 1350 °C and was held for 60 s before being cooled to 560 °C and 580°C. In both conditions, each specimen was isothermally transformed for 1 hour and cooled to room temperature. The heat-treated specimen was then analysed using the electron backscattered diffraction (EBSD) method. As a result, variant preferential selection is more prominent at a higher holding temperature, which coarsened the block and packet boundary and is connected with a low misorientation angle variant
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