The corrosion in 3.5 wt% NaCl solution caused a mitigated weight loss of the aluminum alloy 7050 (AA7050) under cavitation erosion condition. The mechanism was observed using high-resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), electro back-scattered diffraction (EBSD), and potentiodynamic polarization. Both in deionized water and in 3.5 wt% NaCl solution, the cavitation erosion degradation of the AA7050 was mainly attributed to fatigue fracture like peeling off of surface layer materials. The corrosion significantly mitigated the weight loss of AA7050 under cavitation erosion condition because the loose surface oxide film (generated by corrosion) dissipated the cavitation impact energy and therefore alleviated the stress concentration on the alloy surface.

中文翻译：

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AA7050 铝合金在 3.5 wt% NaCl 溶液中的空蚀——第 1 部分：腐蚀缓解效应

3.5 wt% NaCl 溶液中的腐蚀导致铝合金 7050 (AA7050) 在空蚀条件下重量损失减轻。使用高分辨率透射电子显微镜（HRTEM）、X射线衍射（XRD）、X射线光电子能谱（XPS）、电背散射衍射（EBSD）和动电位极化观察该机制。在去离子水和3.5 wt% NaCl溶液中，AA7050的空蚀降解主要归因于表层材料剥落等疲劳断裂。腐蚀显着减轻了空蚀条件下AA7050的重量损失，因为疏松的表面氧化膜（腐蚀产生）消散了空化冲击能量，从而减轻了合金表面的应力集中。