Short Time Dilatometry Quench System Analyses

Abstract Dilatometry test systems are commonly used for characterizing the transformation behavior in steels using induction heating for the heating source and gas flow for the cooling source. In these systems, the steel test article is assumed to have a uniform temperature throughout the sample. The accuracy of this assumption depends on the design of the induction heating and gas cooling systems, as well as the time scales for heating and cooling. Previous papers by the authors have shown the variations in temperature that occur during heating and cooling for a TA Instruments DIL805 dilatometer (dilatometer). Investigations were carried out for development of an improved heating/cooling system for this dilatometer using electromagnetic and thermal analyses for the induction coil and CFD analyses for the high-pressure gas cooling system. Electromagnetic analyses showed that a novel cooling system could be incorporated, though higher power would be required to maintain the same heating rate. While the improved cooling system showed promise on an idealized basis, full CFD modeling shows that the system would not provide improved cooling due to complex flow dynamics.