The results were presented of research on the influence of hot plastic forming parameters on the deformability and structure of a Fe-Ni austenitic alloy. The research was performed on a torsion plastometer at 900 to 1150C, at strain rates of 0.1 and 1.0/s. Plastic properties of the alloy were characterized by the worked out flow curves and the temperature relationships of flow stress and strain limit. The structural inspections were performed on microsections taken from plastometric samples after so called freezing. The stereological parameters as the recrystallized grain size, inhomogeneity and grain shape were determined. Functional relations between the Zener-Hollomon parameter and the peak stress and the mean grain size were developed and the activation energy of the hot plastic deformation was estimated. Examination of the sub-structure by transmission electron microscopy allowed the calculation of structural parameters: the average sub-grain area and the mean dislocation density. A detailed investigation showed that the sub-structure was inhomogeneous and consisted of dense dislocation walls, sub-grains and recrystallized regions.

The Hot-Deformability and Quantitative Description of the Microstructure of Hot-Deformed Fe–Ni Superalloy. K.J.Ducki, K.Rodak: IOP Conference Series - Materials Science and Engineering, 2011, 22[1], 012011