The Effect of Particle Size and Spacing on Creep of Two-Phase Copper–Cobalt Alloys

AbstractThe effects of variations in particle diameter and spacing on the steady creep rate (έ s ) of three copper–cobalt alloys containing 0·88, 2·48, and 4·04%Co have been studied over a range of stresses at 712 K. At constant particle size and spacing, the stress (σ) and temperature-(T) dependence of έ s for each alloy can be described as ɛ ˙ S = A σ n exp − Q c / R T A change in stress exponent, n, and activation energy for creep, Q c , occurs at a stress comparable with the macroscopic yield stress. It is proposed that with stresses < YS, when n ≃ 4·5 and Q c ≃ 140 kJ/mo...