E. Troell, H. Kristoffersen, J. Bodin, S. Segerberg, I. Felde
April 27, 2013
Abstract
One of the most critical parts of the heat treatment process, and usually the least controllable one, is the quenching operation. Improper selection or application of a quenching medium, or a drift in its cooling characteristics during its lifetime, may result in products that do not meet specifications and therefore give rise to substantial additional costs for e.g. straightening, rework, rejection, delayed deliveries and, sometimes, lost goodwill for the heat treater. A greater awareness of the importance of the quenching process came with the introduction in the last couple of decades of ISO and ASTM standards for testing cooling media (hardening oils and polymers), and commercial instruments for testing compliance with these standards. In 2003, a new, advanced system – ivf SmartQuench – was introduced which has three main features: a small, handheld data acquisition unit, advanced computer software and wireless data transmission between the data acquisition unit and the computer. The design facilitates in-situ testing in quench tanks and testing in laboratories. Recently, this system has been extended with a unique software module that allows calculation of heat transfer coefficients (e.g. for the ISO 9950 probe) by the inverse method, and calculation of hardness and microstructure in a cross-section of steel samples.