On the configurational force associated with blocked slip bands at grain boundaries in {\alpha}-Ti

TL;DR

This paper introduces a configurational force framework to quantify the energetic severity of blocked slip bands at grain boundaries in titanium, revealing that local stress geometry influences slip extension beyond traditional geometric criteria.

Contribution

It applies a novel energetic descriptor based on a domain integral to measure the local driving force for slip extension, surpassing conventional geometric metrics.

Findings

Configurational force correlates with slip extension tendency.

Local stress geometry influences energetic favorability.

Decoupling observed between geometric metrics and energetic response.

Abstract

Grain boundaries can block slip-band propagation and generate intense local stress and strain fields that influence subsequent deformation and damage initiation in polycrystalline metals. Conventional geometric criteria, such as Schmid factor and slip-transfer parameters, describe crystallographic compatibility but do not quantify the energetic severity of a blocked slip event. Here, we apply a configurational force framework to high-angular-resolution electron backscatter diffraction (HR-EBSD) measurements obtained from a blocked slip band in commercially pure titanium. By evaluating a J-type equivalent domain integral from the measured elastic field, we quantify both the magnitude and directional dependence of the local energetic driving force associated with the stress localisation; thus, providing an energetic descriptor of the tendency for deformation to extend into the neighbouring grain. The results show a marked decoupling between conventional geometric metrics and the configurational force response, indicating that the local stress-localisation geometry strongly influences which crystallographically admissible extension directions in the neighbouring grain are energetically favoured. The framework provides a physically grounded basis for quantifying blocked-slip severity and for motivating future in situ studies aimed at defining a critical transfer threshold for transfer or cracking.