Deposition of HA-based coatings on bio-inert substrates by various deposition methods for improved bio-mechanical properties

Abstract

Hydroxyapatite (HA) is an attractive bioactive material in the biomedical field due to its chemical composition and structure which are similar to the mineral components of natural bone. It is a highly bio-compatible and osteo-conductive material. However, the low bending strength and fracture toughness of pure HA restrict it from implant applications. Although bio-inert materials such as titanium alloy and bio-grade stainless steel have excellent mechanical properties, they show poor osteo-conductivity. Coating of HA applied to these metallic materials can be a solution to the problem. The HA-coated metallic implant can have superior mechanical and biological characteristics. HA powder can be synthesized from chemical reagents or biogenic materials by using various routes. Chemical composition and other properties of biogenic material are preserved in the synthesized biogenic-derived hydroxyapatite. The HA powder is deposited as a coating on bio-inert metals for biomedical implant applications by using several deposition methods. In this chapter, several techniques such as plasma spray, electrophoretic deposition, sputtering deposition, pulsed laser deposition, spin coating, ion beam assisted deposition, sol-gel deposition, electrodeposition, cold spray, and suspension spray techniques which were used to deposit HA coatings are discussed thoroughly. The characteristics of the HA coatings in terms of their microstructure, phases, mechanical properties, and biological behavior are described in detail. © 2023 Nova Science Publishers, Inc.