Characterization of Newly Developed Zinc Composite with the Content of 8 wt.% of Hydroxyapatite Particles Processed by Extrusion.

Jan Pinc,Klára Hosová,Vojtěch Hybášek,Jaroslav Čapek,Filip Průša,Dalibor Vojtěch,Jan Maňák

doi:10.3390/ma13071716

Abstract

Zinc and its alloys belong to a group of biodegradable materials, which can be potentially used for the preparation of temporary orthopedic implants. The research of biodegradable zinc materials revealed a lot of limitations; however, the new processing approaches of those materials can enhance their properties, which are insufficient for now. In this study, the zinc composite with 8 wt.% of hydroxyapatite (Zn/HA8) prepared for the first time by extrusion process was characterized from the point of view of the structural, mechanical and corrosion properties. The extrusion process led to good integrity of the interfaces between the zinc and hydroxyapatite particles. Mechanical behavior confirmed the role of hydroxyapatite as a defect in the material structure, which led to a decrease of the Zn/HA8 mechanical properties by approximately 30% (compressive yield strength (CYS) = 154 MPa Zn, 113 MPa Zn/HA8). Despite that, the Zn/HA8 composite showed sufficient mechanical properties for cancellous bone replacement and reached the lower limit for cortical bone. Additionally, the presence of hydroxyapatite caused the preferential precipitation of hydroxyapatite (HA) from the solution and can lead to a significant enhancement of the tissue/implant interface interactions.

Highlights

Zinc and its alloys show remarkable potential to become a new generation of biodegradable materials [1,2,3,4]
The zinc and hydroxyapatite initial powders were characterized in our previous work [29]
The porosities of the extruded samples were calculated according to Equations (1) and (2) and the resulting values were 10% for the composite and 1.1% for the pure zinc (Table 2)

Summary

Introduction

Zinc and its alloys show remarkable potential to become a new generation of biodegradable materials [1,2,3,4] The advantages of those materials, such as an almost suitable corrosion rate or nonparticipation of hydrogen in the corrosion process under the physiological conditions, are well known [5,6]. Some in-vitro studies suggest that pure zinc can exhibit insufficient biocompatibility [8,9]. Those limitations have to be solved and sufficient mechanical, corrosion and biological properties of Zn-based materials have to be achieved before implantation.

Methods

Results

Conclusion