In recent years many different biomedical implants have been created for prolonged usage within the human body. The number of these implants has been steadily expanding. Mechanical characteristics of biomaterials, such as elastic modulus, hardness, tensile strength, and scratch resistance, are essential for implants. Biomechanical incompatibility is associated with implant fracture brought on by mechanical failure. The materials utilized to replace bone must have mechanical qualities comparable to those of bone. Metallic implants deteriorate due to wear, electrochemical breakdown, or a synergistic mix of the two. Biocompatible materials are used to repair or replace joints, fractured, or otherwise damaged bone. Corrosion is the main factor in hip implant failure. These characteristics also contain several other factors, such as solution factors, geometric factors, metallurgical factors, and mechanical factors. The mechanical properties of the implant materials were most important and had a considerable impact on the process of bone restoration. Metals have the highest tensile strength compared to other materials, followed by polymers and ceramics (except for zirconia). There are several issues with the metallic biomaterial that need to be fixed, including the release of harmful substances during metallic corrosion.

Hydroxyapatite (HAp) is still one of the most common bioactive coatings used on metal implants in orthopaedics due to its biocompatibility. The application of HAp to metallic implants can be accomplished using a variety of processes. Plasma spray (PS) coating stands out as the method of choice due to its dependability, affordability, and ability to protect metal surfaces against rust and wear. The use of HAp in medicine has been limited due to the material's unfavorable mechanical characteristics, such as brittleness, a lack of fracture toughness, and inadequate tensile strength. In addition, the remodeling durations of HAp-covered implants are significantly longer, the rate of osseointegration is significantly lower, and no antimicrobial actions or features are present in these implants. The mechanical and biological properties of HAp have been improved by applying various approaches, all of which fall under the category of surface modification tactics. Dopants are one of those strategies that are extremely successful at changing the characteristics and using them in HAp is one of those methods. As a result, this review study aims to consolidate data on implant Hap coating using the plasma spray approach and assess the benefits and problems associated with employing this method. In addition, the paper addresses how altering the structural, chemical, and mechanical features of HAp can assist in overcoming these limitations. In conclusion, it explains how the incorporation of entering the HAp structure can change the features that, when coated using the plasma spraying approach, alter the functionality of the implant.

In the present day and age, engineered materials are making significant strides in their application in the biomedical sector. Human implants have piqued the interest of material and metallurgy researchers due to their unique properties. Machining the materials into implants customized for individual patients has been the standard practice nowadays. To contribute further to the same area, the current research work aims to investigate the machinability of T-L107.12 (a titanium-based human implant) using a non-traditional method called wire electrical discharge machining (WEDM). The machinability of the machining process has been evaluated based on the material removal rate using a roughness meter and the atomic force microscope. The further impact of the machining parameters on the output responses was analyzed based on the statistical analysis.