Modeling, optimization and control of an austenitization furnace for achieving target product toughness and minimizing energy use. (February 2019) - Ganesh, Hari S.
Highlights: A novel model based energy minimization of austenitization furnace is presented. Part temperature distribution is predicted using a radiation-based model. Austenite grain sizes are predicted using time-dependent constitutive relations. Energy input to the system is optimized without compromising product toughness. Abstract: Quench hardening is the process of heating finished or pre-finished steel parts to a specific temperature in order to reach a phase transformation of steel to austenite (austenitization) followed by quenching in oil, water or brine to induce desired metallurgical properties. During this process, both macroscopic quantities such as temperature and heat duty and microscopic variables, such as austenite grain size, determine the quality of the quenched product. In this paper, we propose a novel model-based approach for optimizing the energy input to an austenitization furnace system by capturing the essential physics at both the aforementioned length scales. The model predicts the energy consumption of the system, the part temperature distribution and the austenite grain size distribution as a function of the processing time and processing conditions. An optimization scheme is proposed to minimize the furnace energy consumption without compromising the part heating requirements and product quality.