Analysis of a Three-Dimensional Slip Field in a Hexagonal Ti Alloy from in-situ High-Energy X-ray Diffraction Microscopy Data

TL;DR

This study introduces a novel methodology combining high-energy X-ray diffraction microscopy and crystal plasticity to analyze 3D slip distributions in a Ti-7Al alloy during deformation, revealing networked grain behavior and orientation effects.

Contribution

It presents a new approach for reconstructing 3D slip fields in alloys using in-situ HEDM data integrated with crystal plasticity models, highlighting network connectivity and orientation influences.

Findings

Elevated slip occurs mainly in a large connected grain network.

Favorably oriented grains play a critical structural role.

Rate sensitivities of slip systems influence slip activity patterns.

Abstract

Here we analyze a three-dimensional distribution of crystallographic slip measured in-situ during the uniaxial deformation of hexagonal Ti-7Al. The slip field is reconstructed using a novel methodology that combines spatially resolved lattice orientation fields and grain-averaged stresses measured using high-energy X-ray diffraction microscopy (HEDM) with crystal plasticity. Analysis is performed to explore lattice orientation dependence, stress dependence, and connectivity (network relationships) of grains experiencing elevated amounts of slip. Elevated slip is found to be primarily associated with a single large network of connected grains, and within this network, a clustered group of grains oriented favorably for slip are found to have outsized structural importance. The effect of different rate sensitivities of families of slip systems on reconstructed slip activity is also discussed.