The distribution of Orowan loops and the work-hardening in a dispersion-hardened alloy

Abstract

The distributions of Orowan loops, or eigenstrain, which are formed around each particle during the deformation of a dispersion-hardened alloy, have been numerically calculated and then the work-hardening increments due to the Orowan loops given as the mean internal stress in the matrix as a function of the glide strain, deformation temperature and particle size. The calculation well explains the temperature dependence and particle size dependence of workhardening and the low temperature stationary creep which have been observed in AlSi alloys with silicon particles, except that the work-hardening rate calculated decreases in a narrower temperature range with increasing the deformation temperature than the measured one does. The results obtained are very similar to those obtained in the previous work assuming a uniform distribution of Orowan loops, but the work-hardening rate obtained in the present study decreases more slowly with increasing the deformation temperature than that in the previous work when compared under the same diffusion coefficients for pipe diffusion.