Quenchant Cooling Curves, Rewetting, and Surface Heat Flux Properties of Vegetable Oils

Vegetable oils are currently used for biodegradable and renewable base stocks for quenchant formulation. However, there are relatively few references relating to their true equivalency, or lack thereof, comparative to the quenching performance of petroleum oil-based quenchant formulations. To obtain an overview of the variability vegetable oil quenching performance, the cooling curves and rewetting properties were determined, and the surface heat flux properties were calculated. The vegetable oils that were studied included canola, coconut, corn, cottonseed, palm, peanut, soybean, and sunflower oils. Cooling curves were obtained using the Tensi multiple-surface thermocouple 15 mm diameter by 45 mm cylindrical Inconel 600 probe (Note: Themultiple thermocouple probe was custommanufactured to conform to a drawing provided by: Heattec located at Seglaregatan 1C, 302 90 Halmstad, Sweden). For comparison, similar data was obtained with Houghto-Quench H100, a conventional (slow) petroleum quenchant oil, and Houghto-Quench HKM, an accelerated (fast) petroleum oil quenchant (Houghton International Inc., Valley Forge, PA). The results of this work will be discussed here