Determination of heat transfer coefficients for large scale steel forgings quenched in polymer solutions

The inverse heat conduction method is used to calculate surface heat transfer coefficients (HTCs) as a function of temperature and location during quenching of a complex geometry large steel forging in a static polymer solution. Experimental temperature-time data extracted from the piece were used as input data to calculate the HTC. The geometry was divided into seven different zones (surfaces). An individual HTC, with a high level of experimental confidence, was calculated for each zone by using the inverse heat transfer module of the commercial software DEFORM 2D/3D. These HTCs were then used to predict the through thickness cooling behaviour of the component with a high degree of replication. This method thus appears be useful for further understanding the quenching process on large steel forgings, in general, but could be critical for obtaining accurate cooling behaviour in forgings with non-simple shapes, where one HTC may not be sufficient to describe local cooling behaviour.