Surface modification during hydroxyapatite powder mixed electric discharge machining of metallic biomaterials: a review

ABSTRACT

Surface modifications play a vital role in the performance of bio-implants. Powder mixed electric discharge machining (PM-EDM), a recently developed advanced machining method, can machine and coat the surface of conductive materials at the same time. Hydroxyapatite is a bio-ceramic with a bone-like composition and excellent biocompatibility. Several coating techniques are used to deposit a bio-ceramic layer on the implant surface; however, hydroxyapatite powder mixed–EDM (HAp-EDM) is an electro-thermal process that can be used for surface coating as well as machining of metallic biomaterials. In this review article, surface characteristics such as surface morphology/topography, micro-hardness, phase analysis, recast layer, elemental composition, corrosion/wear resistance, and biocompatibility of the coated surface of an implant after HAp-EDM have been meticulously reviewed. This review also looks at future research opportunities for the HAp-EDM process to meet the high standards required for biomedical materials and their applications in bio-implant manufacturing.

KEYWORDS:

• Metallic biomaterials
• hydroxyapatite powder
• EDM
• coating
• surface modification
• biocompatibility
• phase analysis
• corrosion resistance

Acknowledgements

The authors would like to express their gratitude to the Department of Chemicals and Petrochemicals, Ministry of Chemicals and Fertilizers (DCPC), Government of India, for supporting ‘Centers of Excellence’ in the field of Biomedical.

Additional information

Funding

This research was funded by the Department Of Chemicals And Petrochemicals, Ministry of Chemicals and Fertilizers (DCPC), Government of India (F:No 25012/01/2020-PC-II (FTS:16020)).