Ultrafine- and uniform-grained biodegradable Zn-0.5Mn alloy: Grain refinement mechanism, corrosion behavior, and biocompatibility in vivo

Highlights: • An ultrafine- and uniform-grained Zn–0.5Mn alloy is fabricated via multipass drawing. • D3 alloy features high ductility and could be elongated by up to 245.0% ± 9.0%. • D3 alloy shows uniform corrosion due to the even distribution of MnZn₁₃ phase. An ultrafine- and uniform-grained Zn–0.5Mn alloy (D3 alloy, stands for deformation rate of 99.5%) is fabricated via multi-pass drawing. The alloy features excellent ductility and elongation properties (up to 245.0% ± 9.0% at room temperature). Zn-0.5Mn alloys are composed of two phases, namely, Zn and MnZn₁₃. The MnZn₁₃ phase confers multiple effects during refinement by inducing and pinning low-angle boundaries within grains. Meanwhile, the presence of these phases along grain boundaries prevents the growth of new refined grains. D3 shows uniform corrosion behaviors in c-SBF solution on account of the even distribution of the MnZn₁₃ phase in its microstructure. Animal implantation experiments indicate that D3 has good biocompatibility; it does not cause damage to bone tissue or other organs. Taking the results together, D3 may be developed into a new type of biodegradable material with remarkable elongation and corrosion properties and satisfactory biocompatibility for medical applications.