The effect of plastic deformation upon the substructure of a high-temperature austenitic alloy was presented. Hot-torsion tests were performed at constant strain rates, of 0.1 and 1.0/s, at 900 to 1150C. Examination of the microstructure was carried out by using transmission electron microscopy. Direct measurements of the micrographs permitted the calculation of structural parameters such as the average sub-grain area and the mean dislocation density. A detailed investigation showed that the microstructure was inhomogeneous, and consisted of dense dislocation walls, sub-grains and recrystallized regions.

Sub-Grain and Dislocation Structure Changes in Hot-Deformed High-Temperature Fe–Ni Austenitic Alloy. K.J.Ducki, K.Rodak, M.Hetmańczyk, D.Kuc: Materials Chemistry and Physics, 2003, 81[2-3], 493-5