Following contribution describes characteristic microstructures of the steel 100Cr6 due to transformation after austenitization at 1050 °C and compared after double austenitization (1st state 1050 °C and 2ndstate 830 °C, respectively 860 °C, with inserted holding at the pearlitic state) analyzed by means of transmission electron microscopy (TEM). Consequences on the transformation behavior of this chromium-carbon-alloyed steel are pointed out and examples of the specific literature are discussed. © 2002 Carl Hanser Verlag. All rights reserved.