Table of Contents
Textures and Microstructures
Volume 5 (1982), Issue 3, Pages 127-152
http://dx.doi.org/10.1155/TSM.5.127

On the Stress Dependence of Subgrain Size

1Department of Earth Sciences, Monash University, Clayton, Victoria 3168, Australia
2Department of Materials Engineering, Monash University, Clayton, Victoria 3168, Australia

Received 22 December 1981; Accepted 24 May 1982

Copyright © 1982 Hindawi Publishing Corporation. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

A simple model of the dynamic balance between deformation induced dislocation generation and climb controlled dislocation annihilation in subgrain walls is outlined. This results in a stress-subgrain size relationship which involves various material properties, including the creep stress exponent and the creep diffusivity.

Assuming a fixed slip distance for mobile dislocations, the theory predicts that the subgrain size (d) depends on the stress (σ) as d4σn, where n is the creep exponent, and the proportionality constant is dependent on material properties, temperature, and other environmental variables. This theoretical prediction is satisfactorily compared with published experimental results for a variety of materials.

The implications of the environmental dependence of the stress-subgrain size relation with regard to its use as a palaeopiezometer in naturally deformed minerals are discussed.