Numerical Simulation of Austempering Heat Treatment of a Ductile Cast Iron

• DOI: 10.1007/s11663-015-0511-y
• Publication Date: 2015-11-19T17:00:50Z
• Authors: Adrián D. Boccardo; Patricia M. Dardati; Diego J. Celentano; Luis A. Godoy; Marcin Górny; Edward Tyrała
• Keywords: Fundición nodular; 0203 mechanical engineering; Ingeniería; Hierro fundido; 0211 other engineering and technologies; 02 engineering and technology; Metalurgia; 620

This paper presents a coupled thermo-mechanical-metallurgical formulation to predict the dimensional changes and microstructure of a ductile cast iron part as a consequence of an austempering heat process. To take into account the different complex phenomena which are present in the process, the stress-strain law and plastic evolution equations are defined within the context of the associate rate-independent thermo-plasticity theory. The metallurgical model considers the reverse eutectoid, ausferritic, and martensitic transformations using macro- and micro-models. The resulting model is solved using the finite element method. The performance of this model is evaluated by comparison with experimental results of a dilatometric test. The results indicate that both the experimental evolution of deformation and temperature are well represented by the numerical model.