The evolution in the understanding of the recrystallization phenomena is summarized in this paper. Initially the main developments concerning recrystallization are presented from a historical perspective. Definitions and concepts involving recrystallization are presented regarding it as a solid-state reaction that occurs by nucleation and growth. The recrystallization nucleation mechanisms are subsequently discussed. Finally, the growth step is highlighted, emphasizing boundary and sub-boundary mobilities and the forces acting on the high angle grain boundaries that sweep the microstructure during recrystallization

The present work studies, in a comparative manner, the sigma phase precipitation of three stainless steels: austenitic type 316L (17Cr–12Ni–2·5Mo, wt-%), superferritic type DIN W. Nr. 1·4575 (Nb–28Cr–4Ni–2Mo, wt-%) and duplex type DIN W. Nr. 1·4462 or UNS S31803 (22Cr–5·5Ni–3Mo–0·14N, wt-%). In austenitic stainless steel, the formation of sigma phase occurred both at austenite grain boundaries and inside delta ferrite islands. In superferritic stainless steel, sigma phase occurred both at grain boundaries and in the grain interior. In the ferrites, both in the duplex and in the austenitic steel, sigma phase formation occurred by eutectoid reaction ferrite→sigma + austenite. The tendency towards precipitation of the sigma phase in the three types of steel investigated can be placed in the following sequence: duplex>superferritic>austenitic.

Wrought austenitic stainless steels are widely used in high temperature applications. This short review discusses initially the processing of this class of steels, with emphasis on solidification and hot working behavior. Following, a brief summary is made on the precipitation behavior and the numerous phases that may appear in their microstructures. Creep and oxidation resistance are, then, briefly discussed, and finalizing their performance is compared with other high temperature metallic materials