Hot tensile behavior of a 7046-aluminum alloy: fracture mechanisms and constitutive models

The high-temperature tensile features of a 7046-aluminum alloy are researched by adopting the hot tensile experiments under different forming parameters. The influences of tensile forming parameters upon the flow behaviors and fracture characteristics are dissected. Meanwhile, the improved Hensel-Spittel-Carofalo (HSC) model and long short-term memory (LSTM) model are proposed to reproduce the hot tensile characteristics. Results clarified that the dominant fracture characteristics contain the nucleation/coalescence of dimples, the progress of serpentine sliding and the formation/regeneration of tenacity nests. The formation of dimples is dramatically aggravated at high strain rate, which deteriorates the necking capability. However, the coalescence of dimples with ascending of tensile temperature, inducing the preferable elongation to fracture. By the verification analysis, the forecasted stresses fit the measured data well, which indicates both the developed LSTM model and the improved HSC model enjoy the preferred reconstructing capability for the high-temperature tensile behaviors of the researched aluminum alloy.