Grain Size Effect on the Martensite Formation in a High-Manganese TWIP Steel by the Rietveld Method

The aim of the present work was to study the effect of austenite grain size (AGS) on the martensite formation in a high-manganese twinning-induced plasticity (TWIP) steel. The results of a quantitative microstructural characterization of the steel by the whole X-ray pattern fitting Rietveld software, materials analysis using diffraction (MAUD), indicated that the volume fraction of alpha(bcc)-martensite increases with increasing AGS. However, the value of the stacking fault probability (P(sf)) does not show a large variation for samples with different values of AGS under water-quenching conditions.