Harper-Dorn Creep — a Myth?

Abstract

Compression creep tests with changes in stress were performed to determine the stress exponent n of the creep rate in the steady state of deformation of pure Al at 923 K, i.e. close to the melting point. The tests confirm that n increases with decreasing σ and ε. The decrease in n to 1 reported in the literature and associated with an autonomous dislocation mechanism of viscous deformation called Harper-Dorn creep could not be reproduced.