Mechanical Properties and Corrosion Behavior of Porous Zn Alloy as Biodegradable Materials

Abstract

The complex stresses experienced by medical-grade porous metals in the physiological environment following implantation as bone repair materials necessitate a comprehensive understanding of their mechanical behavior. This paper investigates the effects of pore structure and matrix composition on the corrosion behavior and mechanical properties of pure Zn. Porous Zn alloys with varying pore sizes were prepared via vacuum infiltration casting. The results showed that addition of Mg elements and an increase in pore size were observed to enhance the strength and elastic modulus of the porous Zn alloy (41.34 ± 0.113 MPa and 0.58 ± 0.02 GPa of the C-Z3AM). However, corrosion tests indicated that specimens with smaller pores and the addition of Mg elements exhibited accelerated corrosion of porous Zn alloys in Hank’s solution. Electrochemical test results show the corrosion resistance rank in order of C-Z5A > C-Z3AM > N-Z5A > N-Z3AM. Additionally, the mechanical retention of porous Zn alloys in simulated body fluids was found to be significantly reduced by the incorporation of Mg elements and smaller pore sizes, the yield strength declines rates of C-Z5A, C-Z3AM and N-Z3AM after 30 days of immersion were 16.7%, 63.7% and 78.2%, respectively. The objective is to establish the role of the material-structure-corrosion-mechanics relationship, which can provide a theoretical and experimental basis for the design and evaluation of Zn and its alloy implanted devices.