Metal/Quenchant Interfacial Heat Flux Transients During Quenching in Conventional Quench Media and Vegetable Oils

摘要

The determination of quench severity and the quantification of the boundary conditions at the metal/quenchant interface would be of considerable utility to the heat treating community. In the present work, an attempt has been made to determine the quench severity of various quench media, including three vegetable oils, by the Grossmann Hardenability Factor method and by estimation of heat flux transients by inverse modeling of heat conduction in 304 stainless steel quench probes. The heat flux transient technique was found to be more accurate than the Grossmann technique in assessing the severity of quenching. This finding was supported by the hardness data and microstructure obtained with the quenched steel specimens. New heat flex parameters are proposed to assess the severity of quenching. The boundary heat flux transients during end quenching of AISI 1040 steel specimens were also estimated. The estimated heat flux transients could be used for modeling of heat transfer during quenching. An attempt has also been made in the present work to assess the feasibility of three vegetable oils, namely coconut, sunflower, and groundnut oils, as quenching media. Further investigation is required in this direction to explore the suitability of these oils for industrial heat treating applications. This application would have immense environmental and economical benefits.