Overview of the current issues in austenite to ferrite transformation and the role of migrating interfaces therein for low alloyed steels

Publication date: June 2015 Source:Materials Science and Engineering: R: Reports, Volume 92 Author(s): M. Gouné , F. Danoix , J. Ågren , Y. Bréchet , C.R. Hutchinson , M. Militzer , G. Purdy , S. van der Zwaag , H. Zurob Solid state phase transformations in metals, and more precisely the science of transformation interfaces, is a key point to understand the formation of nano/microstructure, and thus, as a result, many physical properties such as mechanical properties, conductivity, thermoelectric and magnetic properties of materials. Steels are by far the most widely used metallic alloys, and a deep understanding of their microstructure is essential to tailor their service properties. The transformation of high temperature parent austenite to ferrite is one of the main issues controlling the final microstructures, and for more than a century, this has driven metallurgists to investigate in detail this solid state transformation, and, particularly, the details of austenite to ferrite interface migration. In this paper, we review the evolution of the different concepts and experiments developed in the last century to investigate this transformation mechanism. After a brief introduction, most of the physical models developed, which reduce the α/γ interface into a mathematical body with its own properties, are reviewed and discussed with regard to experimental data. The increased availability of highly sophisticated experimental and modelling tools in recent dec...
Source: Materials Science and Engineering: R: Reports - Category: Materials Science Source Type: research