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Biodegradable implants based on Mg (magnesium) alloys have gained increasing
interest due to both their biocompatibility and mechanical properties, making them a
suitable candidate for AZ31 (Mg alloy). Nevertheless, one of the most considerable
challenges faced by Mg alloys in biomedical applications is their fast corrosion rate. In
this study, the potential of using Electrical discharge machining (EDM) to improve the
corrosion and surface properties of AZ31 magnesium alloy for bio-implant application
has been investigated. The study begins with a preliminary section on bio-implants:
their significance; limitations and corrosion complicated issues associated with bioimplants. The literature review provides an overview of several biodegradable
alternatives, outlines the corrosion mechanisms of Mg alloys, and delves into how
alloying elements (copper and titanium) affect the corrosion resistance and mechanical
integrity of Mg alloys. A detailed experimental approach was used where AZ31 alloy
surface properties were altered using EDM. Key EDM parameters such as current,
pulse-on time, pulse-off time, and voltage were optimised using a Taguchi experimental
design. Statistical analysis using tools such as Analysis of Variance was performed on
the coated samples to calculate surface roughness, microhardness and corrosion
resistance. Results following the alloy Electrical Discharge Machining (EDM) with
copper and titanium corrosion resistance coating revealed better corrosion control of
the alloy, paving the way for the use of the alloy as a bio-implant. The present study
can give insights regarding the advanced surface modification of biodegradable Mg alloys, whenever faced with the potential use in biomedical applications that involve
immediate metal degradation after implantation. In vivo evaluations and long-term
corrosion behaviour should be investigated in future studies to ensure the clinical
relevance of the results.