Fixation screws and other temporary magnesium alloy fixation devices are used in orthopedic practice because of their biodegradability, biocompatibility and acceptable biodegradation rates. The substitution of dissolving implant by tissues during the healing process is one of the main requirements for biodegradable implants. Previously, clinical tests showed the effectiveness of Ga ions on bone tissue regeneration. This work is the first systematic study on the corrosion rate and biocompatibility of Mg–Zn–Ga–(Y) alloys prepared by hot extrusion, where Ga is an additional major alloying element, efficient as a bone-resorption inhibitor. Most investigated alloys have a low corrosion rate in Hanks’ solution close to ~0.2 mm/year. No cytotoxic effects of Mg–2Zn–2Ga (wt.%) alloy on MG63 cells were observed. Thus, considering the high corrosion resistance and good biocompatibility, the Mg–2Zn–2Ga alloy is possible for applications in osteosynthesis implants with improved bone tissue regeneration ability.

Mg alloys have mechanical properties similar to those of human bones, and have been studied extensively because of their potential use in biodegradable medical implants. In this study, the influence of different heat treatment regimens on the microstructure and mechanical and corrosion properties of biodegradable Mg–Zn–Ga alloys was investigated, because Ga is effective in the treatment of disorders associated with accelerated bone loss. Solid–solution heat treatment (SSHT) enhanced the mechanical properties of these alloys, and a low corrosion rate in Hanks’ solution was achieved because of the decrease in the cathodic-phase content after SSHT. Thus, the Mg–4 wt.% Zn–4 wt.% Ga–0.5 wt.% Y alloy after 18 h of SSHT at 350 °C (ultimate tensile strength: 207 MPa; yield strength: 97 MPa; elongation at fracture: 7.5%; corrosion rate: 0.27 mm/year) was recommended for low-loaded orthopedic implants.

Magnesium alloys are attractive candidates for use as temporary fixation devices in osteosynthesis because they have a density and Young’s modulus similar to those of cortical bone. One of the main requirements for biodegradable implants is its substitution by tissues during the healing process. In this article, the Mg–Zn–Ga–(Y) alloys were investigated that potentially can increase the bone growth rate by release of Ga ions during the degradation process. Previously, the effectiveness of Ga ions on bone tissue regeneration has been proved by clinical tests. This work is the first systematic study on the microstructure and mechanical properties of Mg–Zn–Y alloys containing Ga as an additional major alloying element prepared by the hot-extrusion process. The microstructure and phase composition of the Mg–Zn–Ga–(Y) alloys in as-cast, heat-treated, and extruded conditions were analyzed. In addition, it was shown that the use of hot extrusion produces Mg–Zn–Ga–(Y) alloys with favorable mechanical properties. The tensile yield strength, ultimate tensile strength, and elongation at fracture of the MgZn4Ga4 alloy extruded at 150 °C were 256 MPa, 343 MPa, and 14.2%, respectively. Overall, MgZn4Ga4 alloy is a perspective for applications in implants for osteosynthesis with improved bone regeneration ability.

The effect of hot rolling on the structure and mechanical properties of three Mg–Y–Zn–Mn alloys was studied depending on the process temperature and the reduction ratio. The original plates of cast WZM111, WZM211, and WZM321 alloys after heat treatment were subjected to rolling from an initial thickness of 7 mm to a final thickness of 0.2 mm at two temperatures, namely 400 and 450 °C. Optical and scanning electron microscopy, the microhardness measurement, and tensile testing were used to characterize the material. The rolling regimes that provide a good balance between the strength and ductility of the alloys were established.

The effect of hot rolling on the microstructure, mechanical, and corrosion properties of the magnesium alloy 96 wt% Mg–2.3 wt% Zn–0.7 wt% Ca–1 wt% Mn was studied. After heat treatment, the original plates of an as-cast alloy were rolled from a 7 mm thickness to a 0.2 mm thickness at two temperatures—300 or 400 °C. It has been established that increasing the rolling temperature from 300 to 400 °C increases the fraction of recrystallized grains in the microstructure and after rolling at 400 °C, the microstructure is fully recrystallized. The best strength–ductility balance of the alloy was obtained after rolling at 300 °C, with a high total percentage reduction of 93–97%: the yield stress, the ultimate tensile strength, and the elongation averaged at 285 MPa, 310 MPa, and 5%, respectively. The alloy after rolling, annealed at 400 °C, shows improved ductility but lower strength: the yield stress, the ultimate tensile strength, and the elongation were 200 MPa, 260 MPa, and 17%, respectively. The strong dependence of corrosion resistance on respect to rolling direction is observed, which can be reduced after heat treatment. The as-rolled alloy and the heat-treated alloy had low corrosion rates in Hanks’ solution of 0.54 and 0.19 mm/year, respectively.