High-temperature deformation and rupture behavior of commercial high strength 7075 Al has been studied under uniaxial, biaxial, and triaxial stress states. Tets were conducted at 648 K, over four orders of magnitude of strain rate. Relatively similar creep behavior was observed under all states of stress, and the stress exponent was found to be approx 5.3. Rupture times for the different stress states are compared with respect to four different mechanistic multiaxial stress parameters, which are each linked to a particular physical mechanism controlling the creep reupture process. The results indicate that the principal facet stress parameter successfully correlates the data over the entire stress range investigated. This suggests that the creep rupture process is primarilycontrolled by cavitation coupled with localized deformation processes along inclined directions.
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