A novel processing route comprising of thermomechanical rolling followed by direct quenching and partitioning (DQP) has been established for developing tough ductile high strength steels with yield strengths ≈1100. MPa. Suitable compositions were designed based on high silicon and/or aluminum contents and the microstructural mechanisms and DQP parameters established through physical simulation on a Gleeble simulator. Based on these results, suitable laboratory rolling trials were designed that also enabled coiling simulation. Desired martensite-austenite microstructures in respect of refined and randomized martensite packets/laths and finely divided austenite resulted in excellent mechanical properties, particularly at low quenching temperatures.
Somani, M. C., Porter, D. A., Karjalainen, L. P., Suikkanen, P. P., & Misra, R. D. K. (2015). Process Design for Tough Ductile Martensitic Steels through Direct Quenching and Partitioning. In Materials Today: Proceedings (Vol. 2, pp. S631–S634). Elsevier Ltd. https://doi.org/10.1016/j.matpr.2015.07.363