Experimental Determination of The Temperature Evolution Within The Quenchant During Immersion Quenching
B. Hernández Morales, A. López Valdéz, H.J. Vergara Hernández, G. Sánchez Sarmiento, A. Gastón, G. E.Totten:
EXPERIMENTAL DETERMINATION OF THE TEMPERATURE EVOLUTION WITHIN THE QUENCHANT DURING IMMERSION QUENCHING,
New challenges in heat treatment and surface engineering – conference in honour of prof. Božidar Liščić (09 – 12 June 2009, Dubrovnik – Cavtat, Croatia)
Experimentally, the steel quenching process is typically studied by inserting thermocouples into a probe or actual part to determine cooling curves. However, this is not always possible. Recently, Kuyucak described an experimental and modeling process involving the measurement of the temperature increase of the quenchant in the vicinity of the cooling metal surface as a function of time in order to compute cooling curves. To explore the possibilities and limitations of this technique, experimental work with a conical-end cylindrical stainless steel test probe quenched in still water at 60 ºC, with thermocouples located within the probe and also in the quenchant, was conducted. It was found that the results are quite sensitive to the proximity of the thermocouple to the surface of the metal as well as to the thermocouple position in the vertical direction. For example, some experiments were performed with two thermocouples in the quenchant (water) – both at the same distance from the probe surface but at different heights and it was learned that data from the lower thermocouple must be used.