Effect of annealing in the range of thermal stability on structure peculiarities of steel Fe-Mo-Nb-V-0.08C processed by high-pressure torsion

E. Astafurova, G. Maier, V. Koshovkina, E. Melnikov, E. Naydenkin, A. Smirnov, V. Bataev, P. Odessky, S. Dobatkin
Abstract
We studied the effect of annealing in the range of thermal stability on the structure of the steel Fe-Mo-Nb-V-0.08C processed by cold high-pressure torsion. After annealing at 500 ° C, the average size of the structural elements (microcrystallites, d = 112 nm) and their size distribution vary slightly compared to the state after torsion, and the microhardness increases up to 6.4 GPa (6.0 GPa after high-pressure torsion). After annealing of the steel, a partial relaxation of the structure and boundaries occurs, as well as the nucleation of thermally activated nuclei of recrystallization, the size of which is close to the size of the microcrystallites and subgrains formed under high-pressure torsion. Along with the particle hardening, this leads to the maintenance of high values of microhardness and submicrocrystalline character of the structure in steel after annealing at 500 °C.
Received: 05 May 2015   Accepted: 17 September 2015
Views: 74   Downloads: 33
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