Fatigue Scatter of 1.2542 Tool Steel after Deep Cryogenic Treatment

What is it about?

Fatigue failure is the most common failure in engineering parts. Therefore, effect of deep cryogenic treatment on the fatigue strength of 1.2542 tool steel has become important. In this study, two groups of specimens were used to investigate fatigue behavior; only one of these groups underwent deep cryogenic treatment in liquid nitrogen for 4 h after hardening treatment in water. The results showed that fatigue limits of both groups were approximately the same; however, scatter of fatigue data was less in the deep cryogenic specimens. Thus, in design process, deep cryogenic specimens can be used with more reliability coefficient; therefore, dimensions of engineering parts are reduced.

Featured Image

Why is it important?

Cryogenic treatment is used for dimensional stability, increased life, and improved wear resistance and hardening of steels. In this process, retained austenite is partly transformed into martensite, as a result of which appropriate locations are obtained for the formation of secondary carbides at low tempering temperatures. Because carbon diffusion is not an issue in the transformation of retained austenite into martensite; but, the transformation is sliding and without any diffusion. The result of this process is increase in the content and population density of secondary carbide particles, which improves bulk hardness and wear resistance.