THERMAL STABILITY AND EXTRA-STRENGTH OF AN ULTRAFINE GRAINED STAINLESS STEEL PRODUCED BY HIGH PRESSURE TORSION

M M Abramova (1) , N A Enikeev (1) , Xavier Sauvage (2) , Auriane Etienne (2) , Bertrand Radiguet (2) , E Ubyivovk (3) , R. Valiev (1)

1 USATU - Ufa State Aviation Technical University
2 GPM - Groupe de physique des matériaux
3 SPSPU - Saint Petersburg State Polytechnical University

Investigations of an ultrafine-grained (UFG) Cr-Ni austenitic stainless steel produced by high pressure torsion (HPT) at room and elevated (400 C) temperatures followed by series of annealing up to 700 C are reported. The grain size of the alloy processed at room temperature (55 nm) was found to be about twice lower than the grain size of the alloy (90 nm) processed at elevated temperature. Besides, both as-processed states demonstrated a very high value of microhardness (~590 Hv) , while the steel in initial quenched state had the microhardness about 155 Hv. It is shown that the hardness of the steel in both UFG states does not decrease with annealing up to 650 C, and even a certain increase in hardness was observed for the steel produced at room temperature. At higher temperature (700 C), the recrystallization starts, and precipitation was observed.

Domaines: Science des matériaux [cond-mat.mtrl-sci]

M M Abramova, N A Enikeev, Xavier Sauvage, Auriane Etienne, Bertrand Radiguet, et al.. THERMAL STABILITY AND EXTRA-STRENGTH OF AN ULTRAFINE GRAINED STAINLESS STEEL PRODUCED BY HIGH PRESSURE TORSION. Reviews on Advanced Materials Science, 2015. ⟨hal-02108201⟩