Trajectory and Crystallography of Crack Growth in Austenitic Steel after LCF Tests

Abstract:

Analysis of microcrack and mesocrack formation in austenitic steel thin filmsprepared after low-cycle fatigue (LCF) testsfrom bulk samples is presented using TEM techniques. Location, orientation and interaction of microcracks with microstructure components of the steel were determined. Plastic zone ahead of mesocrack tip and the structure changes in it were analyzed. Crystallography of slip bands and deformation twins and their relation with the microcrack propagation direction were also determined. The impact of grain anisotropy and inhomogeneous distribution of stress relaxation ahead of mesocrack tip in plastic zone were considered. Influence of sizes of mesocracks [ and microcracks and their relation with the trajectory and crystallography of propagation are also discussed.

• Periodical: Key Engineering Materials (Volumes 592-593)
• Pages: 793-796
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.592-593.793
• Online since: November 2013
• Authors: Tamaz Eterashvili, Temur Dzigrashvili, M. Vardosanidze
• Keywords: LCF, Mesocrack, Microcrack, Plastic Zone, TEM, Thin Film, Twins

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