The effect of high-pressure torsion on microstructure and strength properties of high-nitrogen austenitic steel

E.G. Astafurova, M.S. Tukeeva, V.A. Moskvina, N.K. Galchenko, I.A. Bataev, V.A. Bataev
Abstract
In this paper, we investigate the microstructure and microhardness of high-nitrogen austenitic steel after high-pressure upset and high-pressure torsion (6 GPa) at room temperature. As the result of deformation, steel microhardness increases by 1.5 times after high-pressure torsion per one revolution while the distribution of microhardness is quasi-homogeneous across the disks. The level of solid solution hardening of steel remains high after deformation processing, and the main mechanisms determining fragmentation of the steel structure are slip, twinning, formation of localized deformation microbands, and precipitation hardening.
Received: 16 December 2014   Accepted: 30 December 2014
Views: 134   Downloads: 26
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