Deformation Induced Ferrite Transformation in Microalloyed Steels: Theory and Application

Deformation Induced Ferrite Transformation (DIFT), i.e. transformation occurs during deformation applied in the temperatures above Ar3, has received wider attention since it has been proved to be a very effective way to produce ultrafine grained ferrite in low carbon steels. Although numerous works have been done on this topic in the past decade, the systematic works on DIFT in microalloyed steel, especially on the role of microalloying elements are still lacking compared with those in plain carbon steel. In this paper, the common features of DIFT will reviewed firstly, then an attempt will be made to elucidate the role of microalloying elements (niobium and vanadium) in DIFT, and the application of DIFT technology in microalloyed steels will be presented finally.