Discussions on Segerberg Formula Concerning the Hardening Power of Quenchants
Chen Chunhuai,Zhou Jing'en
(School of Material Science and Engineering,Xi'an Jiaotong University,Xi'an 710049,China)

Abstract: The cooling curves of 10 different kinds of quenching oils and the hardness of samples quenched in the oils have been measured. It was shown that the hardening power calculated from Segerberg formulagave better agreement with test results than the transition temperature from vapor stage toboiling stage and the maximum cooling speed. The hardening power also showed a better agreement with the measured value for carbon steel than for alloy steel. Based on theidea "Keeping rapid cooling within a specific temperature range that varies with different steels is a key for steel hardning"revised formulas for carbonand alloy steels respectively were put forward. The test results suggeste thatthe revised formulas are better than the original one.
Keywords: quenchants;cooling curve;hardening power;Segerberg formula