5th International High Manganese Steel Conference - HMNS 2022

The changes in the martensite structure of 0.1-0.2%C-2%Si-5-7% Mn steels with a decrease in the prior austenite grain size were investigated. Particularly, the austenite grain size, at which the single variant martensite was formed, was investigated. When the prior austenite grain size was 2 micrometers, martensite with a single variant (single block) structure was formed. These results...

Abstract:
Samples from a medium manganese thermomechanical processed steel sheet show strongly preferred crystallographic orientations far from the random distribution. For the quantification of the retained austenite phase, a novel X-Ray diffraction (XRD) based method is presented that calculates the phase fraction from the measured texture data. By a geometrical averaging procedure in a...

Medium Mn steels is a family of new steels which present ground-breaking properties due to their ultra-fine ferritic matrix and a high amount of retained austenite when processed through intercritical annealing. The high fraction of austenite is enabled thanks to carbon and manganese partition between austenite and ferrite at high temperature. Controlling the enrichment and the stability of...

In recent years, most of the studies on medium-Mn steels have focused on the chemical compositions, microstructural evolution, mechanical properties, and heat treatment schedules with different C and Mn contents. The micro/nano scale grain size of medium Mn steel after austenite reverse transformation (ART) provides a challenging situation to characterize the microstructure and evaluate...

3rd generation AHSS (advanced high-strength steel) family encompasses different innovating microstructure concepts, among which medium Mn steels. They have ground-breaking properties due to their particular microstructures containing a nanostructured ferritic matrix and a large amount of metastable retained austenite. Under mechanical solicitation, strain induced martensitic transformation of...

Third generation Advanced High Strength Steels (AHSS), among which medium Mn steels, have potential applications for the automotive industry, due to their high balance between strength and ductility and their excellent forming properties. These good mechanical properties are possible thanks to the presence of a high amount of metastable retained austenite, which will transform into martensite...