Modern industrial development has put forward higher demands on the performance of metallic structural materials, especially in terms of light weight, high strength and corrosion resistance. All of these characteristics are of particular importance in transportation fields. As one of the most representative structural materials, aluminum and alloys have exhibited significant advantages in light weight. Most of the alloys are prominently featured in one specific aspect. The overall performance still needs to be improved. In recent years, researchers have developed Al-Mg-Zn(-Cu) alloy, a new wrought aluminum alloy, whose design strategy is known as “crossover alloying”. This novel alloy is an age-hardened Al-Mg alloy with a T-Mg₃₂(Al, X)₄₉ (X is Zn, Cu) phase as the main strengthening phase. This system of alloys exhibits excellent properties in terms of strength and corrosion resistance, which makes it promising for applications in automotive, marine, aerospace and other fields. This paper summarizes the research progress of Al-Mg-Zn(-Cu) alloy, and analyzes the basic methods of microstructural control in terms of composition design and property research. Finally, the future directions of this alloy are proposed.

In this study, Cu-Sn alloys with varying compositions were synthesized using nickel sulfate as a structure-directing agent during electrodeposition. The crystalline structure of the alloys and the influence of nickel sulfate on the morphology were systematically investigated. The corrosion behavior of these alloys was examined in 3.5 wt.% NaCl and 0.1 M HNO₃ solutions using kinetic potential polarization and electrochemical impedance spectroscopy (EIS) techniques. X-ray diffractometry (XRD), scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS) were employed to analyze the corrosion products of the alloys. The result revealed that the absolute value of corrosion potential of Cu₄₃Sn₅₇ alloy prepared by adding nickel sulfate in 3.5 wt. % NaCl solution decreased from 0.259 V to 0.186 V, and the corrosion current density decreased from 9.456 × 10⁻⁶ mA cm⁻² to 1.248 × 10⁻⁶ mA cm⁻². In 0.1 M HNO₃ solution, the absolute values of corrosion potential of Cu₄₃Sn₅₇ alloy prepared by adding nickel sulfate decreased from 0.065 V to 0.028 V, and the corrosion current density decreased from 5.384 × 10⁻⁵ mA cm⁻² to 2.63 × 10⁻⁵ mA cm⁻². This research contributes to the understanding of how structural modification affects the electrochemical performance of Cu-Sn alloys.