Lengthening Kinetics of Bainitic Plates in Iron-Nickel-Carbon Alloys

The experimental growth kinetics of bainitic plates in a series of Fe-6 mass%Ni-0.290.71mass%C alloys were compared with the calculation from Zener-Hillert, Trivedi and Atkinson's edgewise growth theories. All theories can account well for the reported lengthening rates in the temperature range between 230 and 500°C except in the 0.29 mass%C alloy. In this alloy, it may become necessary to consider the carbon-partitionless growth (massive transformation) and the interfacial reaction etc., although the carbon content exceeds the solubility limit in ferrite. The reason why morphological difference between upper and lower bainite does not affect the edgewise growth kinetics is considered.