Stress orientation of second-phase in alloys: Hydrides in zirconium alloys

TL;DR

This paper introduces a model to predict the stress-induced orientation of hydride precipitates in zirconium alloys, combining diffusion and nucleation theories to match experimental observations.

Contribution

It presents a novel kinetic model that describes the evolution of precipitate orientation and volume fraction under stress in zirconium alloys.

Findings

The model accurately predicts hydride orientation under stress.

It aligns well with experimental data.

Provides insights into hydride precipitation mechanisms.

Abstract

A model for precipitation of the plate-shaped second-phase under applied stress is presented. The precipitates in the matrix-precipitate system are represented by their local volume fraction and an orientation parameter that defines the alignment of a precipitate platelet in a given direction. Kinetic equations, based on diffusion theory and classical nucleation theory, are used to describe the time evolution of these two parameters. The model is used to describe the stress orientation of hydrides in Zr-alloys in light of experiments.