Tempering effects on three martensitic carbon steels studied by mechanical spectroscopy
Year: 2008
Type: article
Abstract: Tempering effects have been studied in three martensitic carbon steels by mechanical spectroscopy. The mechanical-loss spectra present a relaxation peak similar to the Snoek-Köster peak in ferrite. The peak amplitude decreases upon tempering, indicating a decrease of the dislocation density. Transition carbides start to precipitate at 380 K in all the three grades. This tends to decrease the mechanical loss and to increase the modulus. Retained austenite decomposes around 520 K in two of the grades. In the third grade, the presence of Si delays this decomposition to 670 K. The decomposition of retained austenite leads to a sudden decrease of amplitude of the relaxation peak and a modulus anomaly. Both these effects can be attributed to a decrease of the dislocation density in martensite, probably associated with the depletion of carbon atoms in the dislocation core. At low frequency, a mechanical-loss peak associated with the decomposition of retained austenite is visible.
Authors: R. Martin, I. Tkalcec, D. Mari, R. Schaller
Institution: École Polytechnique Fédérale de Lausanne
Language: English
Subfield: Mechanical Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W2000410969