Yu-Chi Xia

Creep and Creep-rupture Behavior of 2124-T851 Aluminum Alloy

Abstract High temperature creep and useful creep life behavior of Al-Cu-Mg (2124-T851 aluminum) alloy was investigated by conducting constant stress uniaxial tensile creep tests at different temperatures (473–563 K) and at stresses ranging from 80 to 200 MPa. It was found that the stress and temperature dependence of minimum creep rate could be successfully described by the power-law creep equation. The power-law stress exponent, n = 5.2 and the activation energy for secondary creep, Q = 164 kJ mol−1, which is close to that observed for self diffusion of aluminum (~140 kJ mol−1). The observed values of n and Q suggest that the secondary creep of 2124-T851 aluminum alloy is governed by the lattice diffusion controlled dislocation climb process. A Monkman-Grant type relationship between minimum creep rate and time for reaching 1.5% creep strain is proposed and could be employed for predicting the useful creep life of 2124-T851 aluminum alloy.