HOSSEINI Seyed Mohammad Imam Khomeini International University

Microstructural Evolution During Coiling Process in Thermomechanically- Processed Low-Silicon Multiphase TRIP-Assisted Steels

Co-authors ZAREI-HANZAKI Abbas, YUE Steve

The present work aimed to elucidate the effect of coiling process conditions on micorstructural evolution and resulted mechanical properties of low-Si TRIP-assisted TMCP steels. In this framework, compression samples which were deformed above Tnr and then intercritically annealed, were held isothermally for different time at temperatures below bainite transformation start temperature. The results indicated that prolonging isothermal holding brings about a micorstructure consists of polygonal ferrite, bainite, retained austenite and martensite. Interaction between these microconstituents and shielding effect of martensite were found to play important roles on the stability of retained austenite. Samples held for shorter isothermal holding times appeared to possess optimum balance of strenghth and ductility compared to the samples were held for longer duration.