Abstract The Al-Si-Fe-Mg-Cu-Zn alloy was used to manufacture large, thin-walled parts for 5 G base stations by using the ultrasonic vibration-assisted air-cooled stirring rod rheological die-casting (ACSR + UV R-DC) process. Investigations were performed on the microstructure and corrosion resistance of the ACSR + UV R-DC alloy which was then compared with traditionally die-casting (T-DC) and ACSR R-DC alloys. The results reported that the ACSR + UV R-DC process not only refined the primary α-Al (α1-Al), the eutectic silicon, and the secondary α-Al (α2-Al), but also significantly improved the morphology and distribution of the β-Al5FeSi phase. Pitting corrosion of the alloy mainly originated from the interface between the β-Al5FeSi and the α2-Al. At the initial corrosion stage, the α1-Al and the interface between the α2-Al and the eutectic silicon were not corroded. As the corrosion time increased, the pitting corrosion continued to spread in the eutectic region and connected to form one large corrosion area. Moreover, the corrosion resistance of the ACSR + UV R-DC alloy was better than that of the T-DC and the ACSR R-DC alloys. This was due to the refinement of the eutectic silicon and iron-rich phases, and the reduction of the potential difference between the iron-rich β-phase and the aluminum matrix.

中文翻译：

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超声振动辅助流变压铸工艺制备的新型Al-Si-Fe-Mg-Cu-Zn合金的显微组织细化及耐蚀性提高机制

摘要 以Al-Si-Fe-Mg-Cu-Zn合金为材料，采用超声振动辅助风冷搅拌棒流变压铸(ACSR+UV R -DC) 过程。对 ACSR + UV R-DC 合金的微观结构和耐腐蚀性进行了研究，然后将其与传统压铸 (T-DC) 和 ACSR R-DC 合金进行了比较。结果表明，ACSR+UV R-DC工艺不仅细化了初生α-Al（α1-Al）、共晶硅和次生α-Al（α2-Al），而且显着改善了形貌和分布β-Al5FeSi 相。合金的点蚀主要来源于β-Al5FeSi与α2-Al的界面。在初始腐蚀阶段，α1-Al和α2-Al与共晶硅的界面没有腐蚀。随着腐蚀时间的增加，点蚀继续在共晶区扩散并连接形成一个大的腐蚀区。此外，ACSR+UV R-DC合金的耐腐蚀性能优于T-DC和ACSR R-DC合金。这是由于共晶硅和富铁相的细化，以及富铁β相和铝基体之间的电位差减小。