AN ORIGINAL EXPERIMENTATION ON THE COOLING OF PARTS PER QUENCHING PROCESS

摘要

In order to study the influence of quenching conditions on the part-bath heat transfer, we developed an original experimental method. It is found on the use of parts of the type 'flat plate' that are more suitable to an instrumentation by thermocouple 'in skin' because the cooling remains one dimensional according to the thickness direction. To determine the PBHTC, thermal conditions at the part-bath interface are estimated by a non linear 1D heat conduction inverse technique. We present some experimental results of quenching operations on Inconel 718 at 1100 deg C and 800 deg C in a bath of agitated water carried to 70 deg C. The reproducibility of measurement is good and allows a reliable estimate of the surface thermal conditions. The evolutions of surface heat flux and temperature are coherent with heat transfer theory. The validation of the estimate is carried out by comparing results of simulation with the recordings of temperature carried out on experiments. The average uncertainty of PBHTC is 12,5 percent and present a maximum of 25 percent near the critical point of heat flux. Considering the strong variation of heat transfer during the quenching process, this result is satisfactory.