Dilatometric Study of Phase Transformations in 5 Mn Steel Subjected to Different Heat Treatments
Mateusz Morawiec, Adam Grajcar, W. Zalecki, Carlos García-Mateo, M. Opiela
Abstract
Open-access reader
Mateusz Morawiec, Adam Grajcar, W. Zalecki, Carlos García-Mateo, M. Opiela
Abstract
Open-access reader
The work presents results of phase transformation kinetics of hot-rolled 5% Mn steel subjected to different heat treatments. Three different schedules were introduced: isothermal holding in a bainite region, coiling simulation and intercritical annealing. The evolution of microstructure components was investigated using dilatometric and metallographic analyses. According to obtained results, the medium-Mn steel exhibits high resistance for γ/α transformation during the bainite transformation and coiling simulation (upon cooling from the austenite region). During 5 h isothermal holding, no bainite and/or ferrite formation was detected. This results in the formation of martensite upon cooling to room temperature. Differently, when the steel was subjected to the intercritical annealing at 720 and 700 °C (upon heating from room temperature), a final microstructure consisted of ferrite, martensite and retained austenite. At 700 °C, no fresh martensite formation was detected upon cooling to room temperature. This means that the austenite was enriched in carbon during the intercritical annealing step enough to keep its thermal stability.
OpenAlex reports 21 citations for this work. Citation counts describe recorded attention and do not establish research quality.
A contribution statement is not available in the OpenAlex record.
Method details are not available in the OpenAlex metadata.
Findings are not separately available in the OpenAlex metadata.
Limitations are not available in the OpenAlex metadata.
Application details are not available in the OpenAlex metadata.
The work presents results of phase transformation kinetics of hot-rolled 5% Mn steel subjected to different heat treatments. Three different schedules were introduced: isothermal holding in a bainite region, coiling simulation and intercritical annealing. The evolution of microstructure components was investigated using dilatometric and metallographic analyses. According to obtained results, the medium-Mn steel exhibits high resistance for γ/α transformation during the bainite transformation and coiling simulation (upon cooling from the austenite region). During 5 h isothermal holding, no bainite and/or ferrite formation was detected. This results in the formation of martensite upon cooling to room temperature. Differently, when the steel was subjected to the intercritical annealing at 720 and 700 °C (upon heating from room temperature), a final microstructure consisted of ferrite, martensite and retained austenite. At 700 °C, no fresh martensite formation was detected upon cooling to room temperature. This means that the austenite was enriched in carbon during the intercritical annealing step enough to keep its thermal stability.
Key concepts: Bainite, Austenite, Materials science, Martensite, Metallurgy, Isothermal process, Microstructure, Isothermal transformation diagram