Simulation of Isothermal Nucleation of Austenite in Spheroidite Plain Carbon Steels

Abstract:

The austenitization is a solid phase transformation process accompanied by nucleation and nucleus growth controlled by long-range carbon diffusion. In the course of our work, a method was developed by which spheroidite model structures were constructed such a way that their different parameters (the size of ferrite grains, the average value of carbon concentration, the size of cementite spheroids) could be changed optionally. In addition, a nucleation model of free enthalpy base was created by which the difference between the two different places of nucleation can be distinguished on the basis of their free enthalpy. The effects of structure parameters, interface free enthalpies and temperature on the nucleation rate of austenite were investigated by cellular automaton simulations.

• Periodical: Materials Science Forum (Volume 752)
• Pages: 201-208
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.752.201
• Online since: March 2013
• Authors: Gábor Karacs, András Roósz
• Keywords: Austenitization, Cellular Automaton (CA), Nucleation Rate, Spheroidite

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