IN-PLANE and out-of-plane deformation at the SUB-GRAIN scale in polycrystalline materials assessed by confocal microscopy - Archive ouverte HAL Access content directly
Journal Articles Acta Materialia Year : 2019

IN-PLANE and out-of-plane deformation at the SUB-GRAIN scale in polycrystalline materials assessed by confocal microscopy

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

Abstract

High-resolution digital image correlation (HR-DIC) techniques have become essential in material mechanics to assess strain measurements at the scale of the elementary mechanisms responsible of the deformation in polycrystalline materials. The purpose of this study is to demonstrate the use of laser scanning confocal microscopy (LSCM) coupled with DIC techniques to deepen knowledge on the deformation process of polycrystalline nickel-based superalloy at room temperature. The LSCM technique is capable of detecting both in-plane and out-of-plane strain localization within slip bands at the sub-grain level. The LSCM observations are consistent with previous in-situ scanning electron microscopy (SEM) studies: The onset of crystal plasticity occurs primarily near Σ3 twin boundaries with bulk locations in the elastic domain (macroscopic stress as low as 80% of the 0.2 % offset yield strength (Y.S.0.2%)). This intense irreversible strain localization occurs with either a high Schmid factor (μ > 0.43) or a significant elastic modulus difference between the pair of twins (ΔΕ > 100 GPa). In the plastic deformation domain, transgranular slip activity following slip systems with the highest Schmid factor is mostly responsible for the deformation at the grain level, thus leading to strain percolation. The simultaneous in-plane and out-of-plane deformation assessment via the HR-LSCM-DIC technique was found to be essential for the identification of active slip systems. Finally, the HR-LSCM-DIC technique enabled the quantification of the real glide amplitude involved in the three-dimensional shearing process at the grain level that solely in-plane measurements cannot provide.
Fichier principal
Vignette du fichier
in-plane-and-out-of-plane-deformation.pdf (6.12 Mo) Télécharger le fichier
Origin : Files produced by the author(s)
Loading...

Dates and versions

hal-02064096 , version 1 (29-04-2019)

Identifiers

Cite

J.H. Liu, N. Vanderesse, J.-C. Stinville, T.M. Pollock, P. Bocher, et al.. IN-PLANE and out-of-plane deformation at the SUB-GRAIN scale in polycrystalline materials assessed by confocal microscopy. Acta Materialia, 2019, 169, pp.260-274. ⟨10.1016/j.actamat.2019.03.001⟩. ⟨hal-02064096⟩
111 View
186 Download

Altmetric

Share

Gmail Facebook Twitter LinkedIn More