The tensile response and fracture behavior of an Al-Zn-Mg-Cu alloy: Influence of temperature

Abstract

A high-performance, high-strength, and novel AI-Zn-Mg-Cu alloy in the T7751 condition was deformed to failure in laboratory air environment at ambient and elevated temperatures. Temperature influenced the tensile response of the alloy for both the longitudinal and transverse orientations. Strength decreased with an increase in test temperature, with a concomitant improvement in ductility. Test results indicate the alloy response to be the same for both the longitudinal and transverse orientations. No major change in the macroscopic fracture mode was observed with the direction of testing. Tensile fracture, on a microscopic scale, revealed features reminiscent of both ductile and brittle mechanisms. The microscopic fracture behavior was a function of test temperature. The mechanisms and intrinsic micromechanisms governing the tensile fracture process are discussed in terms of mutually interactive influences of microstructural effects, matrix deformation characteristics, test temperature, and grain boundary failure.