The addition of Y and Zn can substantially improve the mechanical properties of Mg. Favourable processing conditions promote the formation of a Long Periodic Stacking Ordered Structure (LPSO) that provides superior strength without deteriorating the ductility, while the biocompatibility of Mg-Y-Zn (WZ) alloys makes them suitable as biodegradable implant materials.Four alloys were cast with the compositions of Mg-1.8Y-0.6Zn in pure form and with the addition of 1.6 wt. % of Gd, 1 wt.% of Ag and 0.4 wt.% of Ca, respectively. The ingots were homogenized at 400 °C for 24 h and subsequently quenched in water. The indirect extrusion to 10 mm bars was performed at 400 °C with a speed of 1 mm·s-1 at an extrusion ratio of 1:25. The microscopic characterization has shown that the microstructure of the alloys consists of Mg grains and the 18R type LPSO structure forming during solidification. During the homogenization treatment the 14H type LPSO structure precipitates and the existing 18R structure also transform partially to 14H. The addition of Gd and Ag promotes the formation of 14H, while Ca stabilises the 18R structure. The mechanical testing indicates that the unmodified WZ alloy exhibits the highest yield strength, but the alloying additions increase the UTS and the ductility.The degradation rate of the alloys measured in SBF ranges between 0.11±0.3 mm/y and 0.17±0.5 mm/y and also show a good cell viability of SCP-1 mesenchymal stem cells tests.

Ideal Zn-based biodegradable metal bone implants necessitate customizable biodegradable behaviours and improved osteogenic ability, conforming to the individual requirements of specific patients. Although design of implant material composition is a prevalent strategy, its efficacy in modulating the implant’s performance is notably restricted. Structure design has shown efficacy in regulating the performance of bio-inert metal implants, like Ti alloy scaffolds. However, no study has been systematically conducted on the impact of structure design on the performance of biodegradable Zn-based metal scaffolds. The mechanism that how structure design controls the biodegradable performance and osteogenic ability of scaffolds remains unclear. Hence, in this study, Zn-2Mg alloy scaffolds with different porosities and different unit sizes were designed and fabricated to study the influence and the underlying influencing mechanism of structure design on the in vitro and in vivo behaviour of Zn alloy scaffolds.

In this work, bioresorbable zinc-magnesium alloys are 3D-printed by PBF-LB/M. The goal is to manufacture load-bearing, implants (e.g. patient-specific scaffolds or cages) with suitable degradation properties without damage to the surrounding tissue.

Biodegradable metals, particularly zinc (Zn) and magnesium (Mg) alloys, offer significant potential for biomedical applications, especially in temporary implants that gradually degrade within the body. Recent studies demonstrate the feasibility of additive manufacturing (AM) of both materials to address patient-specific solutions with high geometric complexity. This study explores the innovative combination of Zn1Mg and WE43MEO alloys using multi-material AM techniques, aiming to synergize the unique properties of these materials for optimized performance in medical devices. However, to succesfully combine both alloy systems several challenges need to be tackled, e.g. the bonding parameters and the powder deposition accuracy. In the context of this study, the optimum built plate material as well as bonding parameter are identified by analysing the relative density of cuboid specimens. Additionally. the parameters of the recoating unit are optimized towards the layer wise combination of both materials representing the basis of the processing within one printing job.

Zn is a biodegradable metal with intermediate corrosion rates between Fe and Mg, but it is the least studied to date, and the in vivo effects in the medium/long term are not yet fully understood. Studies so far have shown that Zn has good corrosion resistance and acceptable biocompatibility. Still, significant concerns have been raised due to its poor mechanical strength, aging at room temperature, creep effects, and high sensitivity to strain rate. This study determined if the quantity of Mg of Zn-Mg-based alloys in hybrid samples processed through high-pressure torsion alters the effectiveness of PEO. Results support that aspects such as the techniques for obtaining the alloy, composition, and coatings could synergistically promote the degradation behavior and biocompatibility of materials used as biodegradable implants.