Poulumi Dey

Ab initio explanation of disorder and off-stoichiometry in Fe–Mn–Al–C κ carbides

Carbides play a central role for the strength and ductility in many materials. Simulating the impact of these precipitates on the mechanical performance requires knowledge about their atomic configuration. In particular, the C content is often observed to substantially deviate from the ideal stoichiometric composition. In this work, we focus on Fe-Mn-Al-C steels, for which we determined the composition of the nanosized

Combined atom probe tomography and density functional theory investigation of the Al off-stoichiometry of κ-carbides in an austenitic Fe–Mn–Al–C low density steel

\ensuremath{\kappa}

The Role of κ-Carbides as Hydrogen Traps in High-Mn Steels

carbides (Fe,Mn)

Tetragonal fcc-Fe induced by κ-carbide precipitates: Atomic scale insights from correlative electron microscopy, atom probe tomography, and density functional theory

{}_{3}\mathrm{AlC}

Hydrogen-carbide interactions in steels: Ab-initio calculations combined with experiment

by atom probe tomography in comparison to larger precipitates located in grain boundaries. Combining density functional theory with thermodynamic concepts, we first determine the critical temperatures for the presence of chemical and magnetic disorder in these carbides. Second, the experimentally observed reduction of the C content is explained as a compromise between the gain in chemical energy during partitioning and the elastic strains emerging in coherent microstructures.