The bainite transformation: unresolved issues

A great deal of research, over many decades since the discovery of bainite, has revealed substantial information about the mechanism of the bainite transformation in steels. Elements of the theory are now routinely being used in many parts of the world in the design of novel alloys and in the interpretation of a variety of experimental data. However, there remain some difficulties which are holding up technological progress. Two of these, the precipitation of carbides and the formation of bainite from plastically deformed austenite, are reviewed in the hope that further progress can be stimulated, particularly with respect to the development of quantitative models.