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Zn has garnered increasing attention in the realm of biodegradable materials due to its moderate degradation rate and no harmful gas released during degradation. However, the poor mechanical properties of Zn necessitate improvement by alloying and deformation processing. Currently, the primary studied Zn-based alloy systems include Zn-Mg, Zn-Li, Zn-Cu, Zn-Mn, Zn-Ag, and Zn-Ca alloys. Among these alloy systems, Mg is an essential element for the human body with advantages of low cost and good ability to enhance mechanical properties of Zn. Consequently, biodegradable Zn-Mg alloy exhibits fascinating application potential. This paper provides a comprehensive overview of research progress on Zn-Mg alloys by summarizing the effects of composition and deformation processing on degradation properties, biocompatibility, and mechanical properties. Additionally, this paper highlights existing challenges and hopes to offer new perspectives and ideas for researchers engaged in the study of degradable materials. [Display omitted] [ABSTRACT FROM AUTHOR]

Binary Zn–Mg alloys have great potential as biodegradable implants due to their good biological safety and moderate degradation rates. Herein, a new combined process of ECAP plus cold rolling of as-cast Zn–0.6Mg alloy was developed to address its application problem of insufficient mechanical properties and serious localized corrosion. Cold rolling process can break the eutectic phase and refine grains, while deformed grains were dominant with a lot of dislocations. 8-pass ECAP process can refine grains by recrystallization, and the grains were equiaxed with less dislocations. The strength and ductility were greatly improved after cold rolling (CR) or ECAP processing compared with that of as-cast alloy, but the strength still cannot meet the requirement of orthopedic implant materials. After 8-pass ECAP+CR75% (ER) processing, the strength was further improved, which benefited from fine grain strengthening, second phase strengthening, and strain strengthening mechanisms. Tensile yield strength (σ YS), ultimate tensile strength (σ UTS), and fractured elongation of ER alloy were 301.2 MPa, 411.8 MPa, and 28.5%, respectively, which can meet the requirement of orthopedic implants. The eutectic phase fragmentation and grain refinement caused by cold rolling and ECAP process can reduce the galvanic corrosion tendency of the Zn–0.6Mg alloy. The corrosion resistance was further improved after 8-pass ECAP+CR75% processing with the degradation rate of 0.025 mm/y, and the alloy tended to corrode uniformly. • A new combined process of ECAP plus cold rolling (CR) of as-cast Zn-0.6Mg alloy was developed. • 8-pass ECAP+CR75% processing can refine grains and break eutectic phase of Zn-0.6Mg alloy greatly. • The mechanical properties of 8-pass ECAP+CR75% processed Zn-0.6Mg alloy were superior in Zn-Mg alloys. • The 8-pass ECAP+CR75% processed Zn-0.6Mg alloy tended to corrode uniformly. [ABSTRACT FROM AUTHOR]

• Bulk Al 35 Mg 30−x Zn 30 Cu 5 Si x HEAs with low densities were developed to combine high strength with good corrosion resistance. • The hardness and compressive strength of the as-cast HEAs are superior in light alloys. • The HEAs are more resistant to corrosion than conventional Mg-Al based alloys and better with the increase of Si/Mg ratio. Lightweight high entropy alloys (HEAs) have great application potential in automobile and many other fields. Herein, novel low-cost Al 35 Mg 30−x Zn 30 Cu 5 Si x (x = 5,10,15) lightweight high entropy alloys were designed and prepared by electric melting. The microstructures, mechanical properties and corrosion behavior in 3.5 wt% NaCl of the alloys were investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM) equipped with energy dispersive spectrometer (EDS), hardness testing, compressive testing, immersion testing and electrochemical testing. The results show that the as-cast Al 35 Mg 30−x Zn 30 Cu 5 Si x alloys have complex phase structures composed of fcc phase, Al-Mg-Zn phase, Mg 2 Si phase, Si phase and eutectic phase. Although the structures are complex, the alloys exhibit great compressive strength. With the increase of Si/Mg ratio, the content of Al-Mg-Zn phase and eutectic phase decreases, while the content of fcc phase increases, which has a positive effect on the mechanical properties and corrosion resistance of the alloys. [ABSTRACT FROM AUTHOR]