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DUPLEX stainless steels (DSS) having a two-phase microstructure consisting of ferrite and austenite are widely used in corrosive environments such as chemical plants due to their excellent corrosion resistance and strength. However, to enhance the usage of DSS in a wide range of structural applications, proper understanding of the deformation and recrystallization behavior is required particularly in view of the additional complexity arising from the presence of the second phase in the microstructure. Surprisingly, the development of microstructure and texture during deformation and recrystallization in DSS has been studied to a much lesser extent as compared to single-phase austenitic or ferritic steels. Even then, most of the available prior studies on deformation behavior of DSS steels have focussed on the microstructure and texture evolution during cold deformation and subsequent annealing.[1–6] It has been reported that ferrite and austenite in DSS deform independent of each other, leading to a deformation texture similar to the respective single-phase materials.[2] However, few recent investigations have PINAKI PRASAD BHATTACHARJEE, Assistant Professor, M. ZAID, and G.D. SATHIARAJ, Research Scholars, and B. BHADAK, M.Tech. Student, are with the Department of Materials Science and Engineering, Indian Institute of Technology Hyderabad, Ordnance Factory Estate, Yeddumailaram 502205, AP, India. Contact e-mail: [email protected] Manuscript submitted July 8, 2013. METALLURGICAL AND MATERIALS TRANSACTIONS A

shown that the development of the characteristic bandlike morphology having an alternate arrangement of bands of ferrite and austenite can influence the development of texture of the two constituent phases in DSS, particularly in the heavy strain regime.[7–9] The situation may be further complicated by the fact that the starting microstructure and texture prior to cold rolling can significantly affect the subsequent development of microstructure and texture during cold rolling.[10–12] In the present work, the evolution of microstructure and texture during heavy warm rolling of DSS in a wide temperature range is studied. It may be pointed out that the effect of warm rolling on microstructure and texture formation has been energetically studied in single-phase materials.[13–15] However, there are hardly any studies being reported on DSS. From a commercial viewpoint, warm rolling is considered particularly beneficial in realizing new products and reduction in the production cost of hot-rolled strips. Effect of warm rolling is considered interesting particularly due to the fact that ferrite and austenite may show different softening behaviors. It is reported that single-phase ferrite shows recovery (or dynamic recovery)-type behavior, while single-phase austenite is a predominantly recrystallization-type material.[16,17] These differences in the behavior of the two phases can also affect the evolution of microstructure and texture of DSS during warm rolling and subsequent recrystallization, but need to be studied in depth. Th