W. Bednarczyk; W. Chromiński; G. Cios; M. Wątroba; M. Wieczorek-Czarnocka; G. Cieślak; M. Marciszko-Wiąckowska; J. Michler; P. Bała; M. Lewandowska
Journal of Materials Research and Technology 39 (2025) 15-25
Biodegradable Zn alloys require improved strength and thermal stability to meet the demands of load-bearing
biomedical, bioresorbable implants. In this study, a Zn–0.33Li–0.44Mn–0.45Mg (wt.%) alloy was processed by
rapid solidification (RS) followed by high-pressure torsion (HPT), producing a uniform ultrafine-grained matrix
(~140 nm) with a homogeneous dispersion of nanometric Mg2Zn11 precipitates. These precipitates effectively
stabilized grain boundaries and provided precipitation strengthening. Post-deformation annealing up to 300 ◦C
resulted in gradual grain growth without abrupt coarsening, confirming the enhanced thermal stability imparted
by Mg2Zn11. The RS–HPT condition annealed at 250 ◦C for 15 min achieved an ultimate tensile strength of ~507
MPa and a yield strength of ~391 MPa, with a UTS/YS ratio of ~1.3 and measurable strain hardening. Strain-
rate sensitivity remained high in the ultrafine state and decreased only after significant grain growth, consistent
with grain boundary-mediated deformation. These results demonstrate that combining RS, HPT, and tailored Mg
content provides a controllable processing pathway to thermally stable, high-strength Zn alloys, offering strong
potential for bioresorbable load-bearing applications.