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The effects of homogenization temperature at 465 °C and different homogenization times (6h/12h/24h/36/h/48h) on the microstructure and mechanical properties of as-cast 7075 aluminum alloy were studied using optical microscopy (OM), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), transmission electron microscopy (TEM), hardness testing, and tensile testing. The results show that during the initial stage of homogenization, the continuous bright white network of σ-Mg (Zn, Cu, Al)2 phase transforms into a white broken flocculent S–Al2CuMg phase with the dissolution of Zn. In the middle stage, the S–Al2CuMg phase dissolves and Cu diffuses into primary Al7Cu2Fe, accompanied by precipitation of a large amount of dispersed nanoscale MgZn2 phase. With the homogenization time, the Al7Cu2Fe and MgZn2 phase are coarsened. The strength and plasticity of the alloy show a trend of first increase and then decrease. When the homogenization time is 24 h, the ultimate tensile strength (UTS), yield strength (YS), and elongation reach the peak values of 231.1 MPa, 134.2 MPa, and 4.0%, respectively. The phase transformation and dissolution mechanism during the homogenization process of 7075 aluminum alloy provides a scientific theoretical basis for improving the mechanical properties of the alloy.

The impact of wave-induced forces on the integrity of stationary oscillating water column (OWC) devices is essential for ensuring their structural safety. In our study, we built a three-dimensional numerical model of an OWC device using the computational fluid dynamics (CFDs) software OpenFOAM-v1912. Subsequently, the hydrodynamic performance of the numerical model is comprehensively validated. Finally, the hydrodynamic performance data are analyzed in detail to obtain meaningful conclusions. Results indicate that the horizontal wave force applied to the OWC device is approximately 6.6 to 7.9 times greater than the vertical wave force, whereas the lateral wave force is relatively small. Both the horizontal and vertical wave forces decrease as the relative water depth increases under a constant wave period and height. In addition, the highest dynamic water pressure is observed at the interface between the water surface and device, both within and outside the front wall of the gas chamber. The dynamic water pressure at different locations on the front chamber increases and subsequently decreases as the wave frequency increases.