New Design to Provide Absolute Protection Within a Certain Period for Biodegradable Magnesium Alloys

Abstract

Objectives

Magnesium and magnesium alloy materials have excellent potential as biodegradable bone plate implants. However, the practical application of magnesium alloys is limited by their high chemical activity and poor corrosion resistance. Here, we chose a microarc fluorination (MAF) treatment to improve corrosion resistance while enhancing aspects of magnesium alloy properties. The aim of this study was to identify the effect of fixed-point corrosion on the corrosion resistance as well as the mechanical properties of magnesium alloys and to design a new corrosion-oriented model that can provide absolute protection over a period of time.

Material and Methods

MAF treatment is used for surface modification of magnesium alloys to improve the corrosion resistance of magnesium alloys. To investigate the effect of the coating and indentation on the corrosion resistance of Mg alloy, electrochemical corrosion experiments were carried out. It is worth mentioning that in this experiment we measured and analyzed the mechanical properties of the samples, especially the tensile strength.

Results

In the innovative indentation sample test, the coated specimens showed lower tensile strength due to the occurrence of fixed-point corrosion. To avoid the loss of mechanical properties due to fixed-point corrosion, we proposed a new idea (Corrosion-oriented Design). Ultimately, the immersion experiments as well as the mechanical properties analysis concluded that the Corrosion-oriented Design samples could maintain the mechanical properties without detectable loss for a long time.

Conclusion

The Corrosion-oriented Design model can avoid the nuisance of fixed-point corrosion and control the centralized orientation of corrosion. This provides a new direction for the clinical application of magnesium alloys, which may offer a completely stable bone-healing condition in trauma treatment and avoid the drawbacks caused by the previous uncontrolled corrosion.