Microstructure, Mechanical and In-vitro Degradation Behaviour of Zinc-Copper-Reduced Graphene Oxide Reinforced Composites for Tibia Bone Locking Compression Plate

Magnesium and iron-both pure and alloyed-have been thoroughly investigated as potential biodegradable metals for use in medicine throughout the past 10 years. Nevertheless, extensive use of these materials has shown significant limitations in terms of their applicability for therapeutic uses post vehicle accidents or occupant injuries. Zinc (Zn) and its alloys show potential as biodegradable bone implants due to their low breakdown rate and safety in the human body. However, its poor mechanical strength, cyto-compatibility, and slow disintegration rate preclude its employment as an internal fixing material, particularly in load-bearing parts of the skeleton. In the present work, the zinc powder, copper powder and reduced graphene oxide (RGO) powder are wet ball-milled in planetary ball milling machine. The biodegradable Zn-Cu-nRGO (Cu is 4% by wt. and n = 0.1, 0.2% and 0.3%) composite samples are sintered by vacuum sintering. The microstructures and chemical compositions of the Zn-Cu-nRGO composites were characterised using scanning electron microscopy (SEM). In-vitro degradation of Zn-Cu-nRGO composite samples in simulated bodily fluid solution was investigated. It is anticipated that the incorporation of Cu and RGO will yield dependable performance for potential tibia bone locking compression plates under a range of boundary and loading conditions.