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In order to improve the understanding of the hot flow behaviors of as-extruded 7050 aluminum alloy, a series of isothermal compression tests with a fixed height reduction of 60 % were performed at the temperatures of 573 K, 623 K, 673 K and 723 K, and the strain rates of 0.01 s−1, 0.1 s−1, 1 s−1 and 10 s−1 on a Gleeble-1500 thermo-mechanical simulator. Based on both nonlinear and linear estimations of work hardening rate versus strain curves, two phenomenological models have been developed to predict the flow stress values under different hot forming conditions up to the peak stress. The suitability levels of these two models were evaluated by comparing both the correlation coefficient (R) and the average absolute relative error (AARE). R-value and AARE-value for the linear phenomenological model are 0.9995 and 2.18 %, respectively, while the R-value and AARE-value for the nonlinear model are 0.9901 and 10.60 %, respectively. The results showed that the predictions of these two models were in good agreement with the experimental data for 7050 aluminum alloy. Fewer materials constants were involved in the linear model, and the predicting ability of the linear model is stronger than the nonlinear model.

The hot workability of the ultra-high strength steel BR1500HS has been investigated by processing maps. A series of hot deformation tensile tests were carried out on a Gleeble-3500 thermal simulator in the deformation temperature range of 773–1,223 K and strain rate range of 0.01–10 s–1. The obtained flow stress curves reveal that the peak stress increases with the rising of strain rate and decreases with the rising of temperature. Based on dynamic materials model (DMM), the processing maps at the strains of 0.05, 0.10 and 0.15 were developed, and the optimum hot working conditions were recommended as the temperature range of 1,200–1,223 K and the strain rate range of 0.01–0.1 s–1, where the peak power dissipation efficiency is about 37 % revealing the occurrence of typical dynamic recrystallization (DRX). The main instability defects are deformation twinning and micro-crack occurring mainly at the temperature range of 773–873 K with the strain rate higher than 1 s–1. In order to deeply understand the microstructure mechanisms, the Zener–Hollomon parameter is solved, and then the self-diffusion activation energy is compared with the apparent activation energy Q at different deformation temperatures and strain rates.

Limited by the electrostatic interaction, the oxidation reaction of cations at the anode and the reduction reaction of anions at the cathode in the electrocatalytic system nearly cannot be achieved. This study proposes a novel strategy to overcome electrostatic interaction via strong complexation, realizing the electrocatalytic reduction of cyanide (CN−) at the cathode and then converting the generated reduction products into nitrogen (N2) at the anode. Theoretical calculations and experimental results confirm that the polarization of the transition metal oxide cathodes under the electric field causes the strong chemisorption between CN− and cathode, inducing the preferential enrichment of CN− to the cathode. CN− is hydrogenated by atomic hydrogen at the cathode to methylamine/ammonia, which are further oxidized into N2 by free chlorine derived from the anode. This paper provides a new idea for realizing the unconventional and unrealizable reactions in the electrocatalytic system. [ABSTRACT FROM AUTHOR]

Limited by the electrostatic interaction, the oxidation reaction of cations at the anode and the reduction reaction of anions at the cathode in the electrocatalytic system nearly cannot be achieved. This study proposes a novel strategy to overcome electrostatic interaction via strong complexation, realizing the electrocatalytic reduction of cyanide (CN−) at the cathode and then converting the generated reduction products into nitrogen (N2) at the anode. Theoretical calculations and experimental results confirm that the polarization of the transition metal oxide cathodes under the electric field causes the strong chemisorption between CN− and cathode, inducing the preferential enrichment of CN− to the cathode. CN− is hydrogenated by atomic hydrogen at the cathode to methylamine/ammonia, which are further oxidized into N2 by free chlorine derived from the anode. This paper provides a new idea for realizing the unconventional and unrealizable reactions in the electrocatalytic system. [ABSTRACT FROM AUTHOR]

Limited by the electrostatic interaction, the oxidation reaction of cations at the anode and the reduction reaction of anions at the cathode in the electrocatalytic system nearly cannot be achieved. This study proposes a novel strategy to overcome electrostatic interaction via strong complexation, realizing the electrocatalytic reduction of cyanide (CN−) at the cathode and then converting the generated reduction products into nitrogen (N2) at the anode. Theoretical calculations and experimental results confirm that the polarization of the transition metal oxide cathodes under the electric field causes the strong chemisorption between CN− and cathode, inducing the preferential enrichment of CN− to the cathode. CN− is hydrogenated by atomic hydrogen at the cathode to methylamine/ammonia, which are further oxidized into N2 by free chlorine derived from the anode. This paper provides a new idea for realizing the unconventional and unrealizable reactions in the electrocatalytic system. [ABSTRACT FROM AUTHOR]

Limited by the electrostatic interaction, the oxidation reaction of cations at the anode and the reduction reaction of anions at the cathode in the electrocatalytic system nearly cannot be achieved. This study proposes a novel strategy to overcome electrostatic interaction via strong complexation, realizing the electrocatalytic reduction of cyanide (CN−) at the cathode and then converting the generated reduction products into nitrogen (N2) at the anode. Theoretical calculations and experimental results confirm that the polarization of the transition metal oxide cathodes under the electric field causes the strong chemisorption between CN− and cathode, inducing the preferential enrichment of CN− to the cathode. CN− is hydrogenated by atomic hydrogen at the cathode to methylamine/ammonia, which are further oxidized into N2 by free chlorine derived from the anode. This paper provides a new idea for realizing the unconventional and unrealizable reactions in the electrocatalytic system. [ABSTRACT FROM AUTHOR]