Millisecond dynamics of deformation bands during discontinuous creep in an AlMg polycrystal - Archive ouverte HAL Access content directly
Journal Articles Physical Review E Year : 2020

Millisecond dynamics of deformation bands during discontinuous creep in an AlMg polycrystal

(1) , (2, 3) , (2, 4) , (1) , (1) , (1)
1
2
3
4

Abstract

Formation of bands of macroscopic strain localization during staircase creep in an AlMg polycrystal is studied by the acoustic emission (AE) technique and high-speed video-recording with an image acquisition rate up to 50 000 frames per second. The simultaneous measurements by two methods allow to distinguish different types of embryo deformation bands and concomitant AE signals and establish correlations between the band evolution and the acoustic response. It is found that the fastest stages of band formation, associated with its emergence to the surface and subsequent accelerated expansion, generate complex AE bursts in the frequency band ~0.05-1 MHz. The correlations hidden in the complex structure of an individual acoustic burst are investigated by methods of statistical and fractal analysis. On the other hand, relationships between average parameters of various physical responses to discontinuous creep are assessed. Particularly, a close correspondence is found between the envelope of the acoustic burst and the rate of stress change during formation of a single deformation band. Evolution of dynamical behavior of embryo bands with increasing creep stress is discussed. Notably, a qualitative change in the AE waveform observed on approaching the ultimate stress is considered from the viewpoint of anticipation of the oncoming fracture.
Fichier principal
Vignette du fichier
ManuscriptPRE20_compressed.pdf (1.18 Mo) Télécharger le fichier
Origin : Files produced by the author(s)
Loading...

Dates and versions

hal-02994009 , version 1 (07-11-2020)

Identifiers

Cite

A A Shibkov, M A Lebyodkin, T A Lebedkina, M F Gasanov, A E Zolotov, et al.. Millisecond dynamics of deformation bands during discontinuous creep in an AlMg polycrystal. Physical Review E , 2020, 102, pp.043003. ⟨10.1103/physreve.102.043003⟩. ⟨hal-02994009⟩
33 View
84 Download

Altmetric

Share

Gmail Facebook Twitter LinkedIn More