A study of the cooling kinetics of bearing steel in UZSP-1 polymer quenching medium

Abstract

The problem of replacing quenching oils by relatively inexpensive and fireproof media based on water is very important for machine-building plants. The present paper is a study of the possibility of using a UZSP-1 polymer quenching medium for quenching parts of roll bearings from steels of the ShKhl5 type.It is known that the quality of quenching is mainly determined by the cooling kinetics of the part in the entire temperature range, and prrimarily in the pearlite and martensite regions. The cooling rate at every moment of time depends on the nature of the heat-transfer processes that occur on the surface of the part. These processes depend substantially on the nature of the material and the state of its surface.It has been noted in [1] that in cooling of steel parts in aqueous solutions of UZSP-1 the film regime transforms abruptly into a nucleate one. This can have an undesirable effect on the properties of the quenched parts. The first experiments on quenching bearing parts have shown that after cooling in aqueous solutions with different concentrations of UZSP-1 (from 2 to 6%) quenching cracks appear on parts of in a solution of UZSP-1 in free quenching and in quenching with a forced circulation of the cooling medium. We plotted the cooling curves and recorded the process with a videocamera_

Quenching of ball-bearing steels and bearing parts in polymer medium UZSP-1

“…The results of these experiments are considered in detail in [8]. Cracks virtually do not form when races are quenched in a 7% solution of UZSP-1.…”