Abstract

The mechanical integrity of rolled ZM21 Mg was improved by equal channel angular pressing (ECAP) to function as a potential biodegradable bone screw implant. Electron backscattered diffraction (EBSD) revealed deformed grains of 45 µm observed in rolled ZM21 Mg. They were transformed to equiaxed fine grains of 5.4 µm after 4th pass ECAP. The yield strength of rolled and ECAPed ZM21 Mg alloys were comparable. In contrast, 4th pass ZM21 Mg exhibited relatively higher elongation when compared to rolled sample. The mechanical properties of rolled and ECAPed ZM21 Mg were dependant on both grain refinement and crystallographic texture. The rolled and 4th pass ECAPed tensile samples exhibited nonlinear deterioration of mechanical properties when tested after 7, 14, 21 and 28 days immersion in Hank’s solution. The evaluation signifies that regardless their processing condition, ZM21 Mg alloys are suitable for surgical areas that requires high mechanical strength. In addition, the 4th pass ECAP samples were viable to MG-63 cells proving themselves to be promising candidates for future in vivo studies.

Highlights

  • Biodegradable implants degrade in the human body and the degraded products are being consumed or excreted

  • It is apparent that the application of magnesium implants in various surgical areas is being rediscovered

  • The objective of the current study is to improve the biomechanical properties of ZM21 Mg alloy by equal channel angular pressing (ECAP) for orthopaedic implant application

Read more

Summary

Introduction

Biodegradable implants degrade in the human body and the degraded products are being consumed or excreted. The stress-shielding phenomena caused by current metallic implants made of stainless steel or Ti alloy can be minimised As degradable materials, they will not remain in the body as permanent implants and will not require a second surgical operation after healing [6]. Among versatile techniques available ECAP is most preferred This is because it has the dual advantage of improving the bio-corrosion resistance and mechanical integrity of Mg alloys. The degradation behaviour of ZM21 Mg in Ringers solution upto 96 h using electrochemical impedance spectroscopy was evaluated [18] These short time periods are not sufficient in evaluating the long term mechanical integrity of magnesium implants. The objective of the current study is to improve the biomechanical properties of ZM21 Mg alloy by ECAP for orthopaedic implant application

Objectives
Methods
Results
Conclusion
Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call