Simulation and optimisation of an industrial process of sub-critical spheroidization annealing of a 100Cr6 steel

The application of the correct industrial thermal pattern for the spheroiclization annealing process of steel needs a precise control of the temperature evolution in the furnace environment and in the mass of the treated steel, which was formerly wiredrawn. The aim is to design a thermal evolution that promotes a complete annealed globular structure, the absence of the decarburation and of an excessive grain growth on the surface of the treated material. An experimental procedure that allows building of a reliable simulation model of the heating process, has been based on a precise monitoring of the thermal evolution of the furnace environment and on the microstructural characterisation of the treated steel. The thermal pattern estimated by the simulation model has permitted designing of an optimised industrial thermal cycle to reach a high-quality standard of the production.