Influence of high-pressure torsion on the structure and mechanical properties of Zn–1%Fe–5%Mg zinc alloy

Abstract

Currently, scientists search for new materials for temporary implants that can dissolve in the body, which leads to the fact that there is no need for repeated surgery. In the last decade, scientific interest has focused on zinc-based materials because, unlike other metals, it has suitable corrosion rates and good biocompatibility. The paper describes an experiment for the study of the influence of deformation on the microstructure, strength and corrosion properties of an alloy of the Zn–Fe–Mg system. The authors carried out energy dispersive analysis and calculation of the volume fraction of the second phase of the Zn–Fe–Mg zinc alloy. The corrosion properties of the Zn–Fe–Mg zinc alloy with different microstructures (before and after high-pressure torsion) were studied using the gravimetric method under conditions simulating conditions inside a living organism (temperature, corrosive environment composition). During the tests, the corrosion mechanism was determined, its rate and mass loss of the samples were calculated. The relief of the corrosion surface was studied using scanning electron microscopy. It has been found that the destruction of the material in a corrosive environment occurs through a matrix containing the active Mg metal. The results of calculations of the corrosion rate for the original sample and samples subjected to high-pressure torsion differed due to a more even distribution of second phase particles during severe plastic deformation. In this work, by alloying zinc with iron and magnesium, as well as using high-pressure torsion, it was possible to increase the microhardness of the samples to 239.6±8 HV, which is a high indicator for zinc alloys.

Keywords

• zinc alloys
• zn–fe–mg
• biodegradable implants
• high-pressure torsion
• biocompatible materials