Kinetics and Microstructural Control

· In the austempering process the sample is again cooled down rapidly to avoid the nose of the thermodynamic equilibrium transition zone.
· The retained austenite is held at a high enough temperature that stresses are reduced.
· The material is then taken on a normal T-T-T trajectory through the thermodynamic transition zone to give a final bainitic microstructure.

From: Higgins, "Engineering Metallurgy," Arnold (1989)