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Cryogenic treatment is a process of controlled gradual cooling of the workpiece to a
temperature ranging from −60 ◦C to even below −190 ◦C, holding the workpiece at this temperature
and then slowly reheating it to ambient temperature. According to the current state of knowledge, the
purpose of cryogenic treatment is to reduce the concentration of retained austenite by transforming it
into hard martensite under low-temperature treatment. The retained austenite reduction in steels
results in improved hardness, impact strength, and wear resistance. This study involved conducting
comparative tests of the hardness, tensile strength, and impact strength of high-speed steel samples
with and without cryogenic treatment, which made it possible to determine the effect of cyclic
cryogenic treatment on the properties of this steel. In addition to that, machining tests were conducted
to assess the life of a cutting tool edge made from both cryogenic-treated and non-cryogenic-treated
high-speed steel. Also, the austenite concentration in the samples was measured by X-ray diffraction.
Obtained results confirmed that the cyclic cryogenic treatment enhanced all tested properties of the
high-speed steel.
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