Quantifying As-Cast and Homogenized AA7050 Mechanical Properties Through Compression Testing

Abstract

Prior studies of cast AA7050 mechanical property are sparse, and only include the as-cast condition. In order to generate data for simulation of stress development in direct chill (DC) casting, compression tests were performed on AA7050 specimens in both as-cast and homogenized conditions in the temperature range of 20–500 °C at strain rates from 10−4 to 10−2 s−1 to a strain of 0.5. Results from test specimens having round and square cross-sections were compared to each other and to published tensile data. The round specimens are preferred due to less cornering effect. The flow stress-strain data is fit to the Ludwik equation to generate constitutive relations for the flow stress as a function of strain, strain rate and temperature. The microstructural changes from as-cast to homogenized structures lowers the flow stress of AA7050 with the removal of harder eutectic microconstituent. This effect is most significant at an intermediate temperature (200 °C) and decreases with increasing temperature.