Papers by Author: Ranjit Kumar Ray

Abstract: Interstitial free high strength steels (IFHS) are widely used in the automobile sector due to their high strength and excellent formability. However, these properties of IFHS steels are very much dependent on the processing parameters, like hot rolling, cold rolling and annealing. The composition and processing parameters influence the chemistry and morphology of the precipitates formed in these steels, which in turn control the texture and thus the deep-drawability. This review will briefly summarize the findings of the ongoing research in this area. An attempt will also be made to elucidate the correlation of precipitation behavior and texture formation (and thus formability) in these steels.

Abstract: Evolution Texture and microstructure has been investigated in a Fe-14Mn-6Si-9Cr-5Ni shape memory alloy during cold rolling and annealing. The starting solution-annealed material show a nearly random texture with microstructure composed of equi-axed austenite grains with some e martensite plates inside. Cold rolling induces a strong alloy type texture with Brass {011}<211> and Goss {011}<100> as major components. Annealing of the cold deformed material produces a nearly random texture. The microstructural investigation reveals that with increasing cold deformation the amount of stress induced e and a’ martensite volume fraction increases. The electron back scattered diffraction (EBSD) phase mapping shows that reversion of the e martensite starts only after commencement of recrystallization.

Abstract: In this study, severe plastic deformation (SPD) of Ti-bearing interstitial-free steel was carried out by multi-axial forging (MAF) technique. The grain refinement achieved was comparable to that by other SPD techniques. A considerable heterogeneity was observed in the microstructure and texture. Texture of multi-axially forged steels has been evaluated and reported for the first time. The material exhibited a six-fold increase in the yield strength after four cycles of MAF.