Influence of transformation temperature on carbide precipitation sequence during lower bainite formation

Temperature cycling and the rate of the bainite transformation

There is a novel range of steels under development, based on bainite forming at exceptionally low temperatures. The advantage of suppressing the transformation temperature is that incredibly fine platelets of bainitic ferrite are generated which are only 20–40 nm in thickness. This makes the steel strong and in combination with the austenite that is retained, gives a useful range of properties ...

Kinetics of the bainite transformation

A theory is developed for the evolution of bainite as a function of time, temperature, chemical composition and austenite grain size. The model takes into account the details of the mechanism of transformation, including the fact that nucleation begins at the austenite grain surfaces, and that the growth of a sheaf occurs by the repeated nucleation of small platelets. Predictions made using the...

Acceleration of Low - temperature Bainite

Very strong low temperature bainite

Bainite has been obtained by heat treatment at temperatures as low as 125°C in a high carbon, high silicon steel. This has had the effect of greatly re® ning the microstructure, which is found to have a strength in excess of 2.5 GPa together with an ability to ̄ ow plastically before fracture. Such properties have never before been achieved with bainite. In this paper metallographic details are ...

Effect of austenite grain size and bainite morphology on overall kinetics of bainite transformation in steels

The effect of austenite grain size on the evolution of the bainite transformation in steels is not yet certain in spite of many investigations.1–7 Barford and Owen1 reported that the reaction rate was accelerated by decreasing the grain size, because of an increase in the number density of grain boundary nucleation sites. Umemoto et al.2 reported similar results and proposed an equation that de...