On Reliability of Stainless Maraging Steel

Abstract:

The investigation results on the problem of the reliability of high-strength low-carbon maraging steel products have been generalized. The influence of a method for remelting on the reliability behavior is shown and the ways for the reliability behavior improvement are suggested. The study of the reasons for decreasing KCU during heat treatment shows that in addition to the precipitation of phases causing brittleness at cooling, chromium zones at heating, and formation of chemical and structure inhomogeneity in the two-phase region, the main reason is the remelting method with the parameters which predetermine the variation in grain size in the structure, a small number of interstitial elements (IE), retained austenite in the structure, and lower level of KCU of the steel prepared by VAR both after quenching and after TST. Shows influence of the quenching temperature on the amount of retained austenite and level of impact strength (KCU), of the time of aging on the work of the crack development (KCV) at the temperature of maximal development of brittleness in steel 08Cr15Ni5Cu2Ti and on the position of brittleness transition temperature prepared by ESR and VAR. After cooling down to the liquid nitrogen temperature, the VAR-steel is less liable to brittle fracture after maximal strengthening aging and more reliable after 1.5h-aging (KCV is twice as much as that in ESR-steel despite the low KCU level). The science-based regimes are developed for stamped semi-finished items from steel 08Cr15Ni5Cu2Ti allowing guaranteeing the proper quality and reliability of functioning of the items made from them.

• Periodical: Solid State Phenomena (Volume 265)
• Pages: 134-140
• DOI: https://doi.org/10.4028/www.scientific.net/SSP.265.134
• Online since: September 2017
• Authors: Tat’ana M. Makhneva*, V.B. Dement’yev, S.S. Makarov
• Keywords: Austenite, Ductile-Brittle Transition, Gas Saturation, Impact Strength, Interstitial Elements, Maraging Steels, Remelting, Thermophysical Properties

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DOI: 10.1007/s11041-012-9436-0

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