A method for determining the quenching effect of a quenching medium, in particular in the case of haerten of steel

摘要

For implementing such method, there is used a steel sample having a ratio V/A comprised between 2 and 12 mm (y = volume, A = surface). The hardness of the sample after tempering is determined at least on one spot located under the sample surface where the cooling speed during tempering is approximately proportional to the thermal flux density at the surface (location of the mean integral temperature). Thereafter, the cooling speed //c//c///ct resulting from the measuring values of the hardness by means of the sample characteristics for the temperature deviation //c//c which is appropriate for the tempering, is determined. The formula Q = k.//c//c///ct gives the mean value of the thermal flux density Q at the surface of the sample, which is used as a parameter for the tempering (k = constant proper to materials for samples).