Strain Rate Contribution due to Dynamic Recovery of Ultrafine-Grained Cu–Zr as Evidenced by Load Reductions during Quasi-Stationary Deformation at 0.5 Tm

0517145 - ÚFM 2020 RIV CH eng J - Článek v odborném periodiku
Blum, W. - Dvořák, Jiří - Král, Petr - Eisenlohr, P. - Sklenička, Václav
Strain Rate Contribution due to Dynamic Recovery of Ultrafine-Grained Cu–Zr as Evidenced by Load Reductions during Quasi-Stationary Deformation at 0.5 Tm.
Metals. Roč. 9, č. 11 (2019), č. článku 1150. E-ISSN 2075-4701
Institucionální podpora: RVO:68081723
Klíčová slova: Cu–Zr * ECAP * ultrafine-grained material * deformation * dynamic recovery * transient * load change tests
Obor OECD: Materials engineering
Impakt faktor: 2.117, rok: 2019
Způsob publikování: Open access
https://www.mdpi.com/2075-4701/9/11/1150/htm

During quasi-stationary tensile deformation of ultrafine-grained Cu-0.2 mass%Zr at 673 K and a deformation rate of about 10−4 s−1 load changes were performed. Reductions of relative load by more than about 25% initiate anelastic back flow. Subsequently, the creep rate turns positive again and goes through a relative maximum. This is interpreted by a strain rate component ϵ ̇-
associated with dynamic recovery of dislocations. Back extrapolation indicates that ϵ ̇- contributes the same fraction of (20 ± 10)% to the quasi-stationary strain rate that has been reported for coarse-grained materials with high fraction of low-angle boundaries, this suggests that dynamic recovery of dislocations is generally mediated by boundaries. The influence of anelastic back flow on ϵ ̇- is discussed. Comparison of ϵ ̇- to the quasi-stationary rate points to enhancement of dynamic recovery by internal stresses. Subtraction of ϵ ̇- from the total rate yields the rate component ϵ ̇+ related with generation and storage of dislocations, its activation volume is in the order expected from the classical theory of thermal glide.
Trvalý link: http://hdl.handle.net/11104/0302509