Development of grain-scale slip activity and lattice rotation fields in Inconel 718

Jonathan M. Hestroffer, Marat I. Latypov, Jean Charles Stinville, Marie Agathe Charpagne, Valery Valle, Matthew P. Miller, Tresa M. Pollock, Irene J. Beyerlein

Research output: Contribution to journalArticlepeer-review

1 Scopus citations

Abstract

Using a combination of in-situ high-resolution digital image correlation (HR-DIC), Heaviside-DIC method (H-DIC), and crystal plasticity finite element (CPFE), we investigate the evolution of intragranular lattice rotations and slip activity during monotonic and cyclic loading in a high performance, polycrystalline face centered cubic material. The CPFE employs a quasi-3D model microstructure, which is a highly resolved mirror representation of the experimental in-situ test sample. In agreement, the measurements and calculations reveal that most grains, regardless of their size and lattice orientation, develop intragranular lattice rotation gradients that span the grain. For a small cluster of grains on the deformed material, we perform HR-DIC analysis of slip lines to demonstrate agreement in the active slip systems and changes in this local slip activity across the individual grains. The combined analysis reveals that deforming grains are divided into sub-granular regions of uniform lattice rotation and these regions are most often associated with only one or two active slip systems. The gradient lines that divide them correspond to changes in the predominant slip system. The model is used to examine the evolution of intragranular lattice rotation in a single fully reversed tension-compression cycle. The calculations indicate that intragranular gradients intensify during the reverse loading path as nearest neighboring regions appear to shed lattice rotation, increasing the lattice rotation in some regions, while shutting down rotation in neighboring regions. These findings provide insight into the irreversible changes that develop within deforming grains at the scale of the grain, particularly the heterogeneous development of intragranular lattice rotation in early stages of deformation, which could serve as precursors to localization.

Original languageEnglish (US)
Article number117627
JournalActa Materialia
Volume226
DOIs
StatePublished - Mar 2022

Keywords

  • Crystal plasticity
  • Grain boundaries
  • High-Resolution digital image correlation
  • Microstructure
  • Superalloys

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Ceramics and Composites
  • Polymers and Plastics
  • Metals and Alloys

Fingerprint

Dive into the research topics of 'Development of grain-scale slip activity and lattice rotation fields in Inconel 718'. Together they form a unique fingerprint.

Cite this