In this work, the microstructure evolution of 2519 aluminum alloy was studied at elevated temperatures by the isothermal interrupted hot compression tests on the Gleeble 1500. A static recrystallization kinetic model was established based on the modified Johnson-Mehl-Avrami-Kolmogorov (JMAK) equation and the microstructures of the alloy were analysed by the optical microscope (OM) and transmitted electron microscope (TEM). The finite element method (FEM) with DEFORM-2D was used to investigate the microstructure evolution of 2519 aluminum alloy in multi-pass hot compression process. The results show that the recrystallization fraction at the centre of specimen was larger than that of the surface. With pass increasing from 1 to 4, the average recrystallization fraction increases from 45.5% to 76.4% and the percentage of recrystallization fraction increases as the pass increases, which are well agreement with the experimental results.

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We show the usefulness of frame-based characterization and control [PRX Quantum 2, 030315 (2021)] for non-Markovian open quantum systems subject to classical non-Gaussian dephasing. By focusing on the paradigmatic case of random telegraph noise and working in a digital window frame, we demonstrate how to achieve higher-order control-adapted spectral estimation for the noise-optimized dynamical decoupling design. We find that, depending on the operating parameter regime, control that is optimized based on non-Gaussian noise spectroscopy can substantially outperform standard Walsh decoupling sequences as well as sequences that are optimized based solely on Gaussian noise spectroscopy. This approach is also intrinsically more resource-efficient than frequency-domain comb-based methods.

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