Abstract
Biomaterials are natural or synthetic in origin materials ‘other than drug’ or the combination of two or more materials that can be used for some period for the replacement or treatment of any organs, tissue, or body. Metallic biomaterials like titanium, stainless steel, and cobalt alloys are notable materials that are adapted and used for medical applications purpose due to their favorable properties such as toughness, relatively low rate of corrosion, and excellent strength. Biomaterials are essential for the replacement of human joints and requires a long period of time such as 15 years to 20 years for older ages and more than 25 years above for younger age patients to serve as implant in their body and therefore, it is necessary to prolong the service life of biomaterials. In this study, the surface modification process was used for the enhancement of existing materials to improve the surface properties of the samples. For this research work, radio-frequency magnetron sputtering was considered for the deposition of the Hydroxyapatite (HAP) thin-film coating on stainless steel. This is due to its potential surface modification capability of high deposition rate, strong bond affinity, low cost of production, and capability to deposit insulating materials since Hydroxyapatite is known to be a good reinforcement for surface modification due to its favorable properties such as excellent bioactive and biocompatibility. Therefore, RF- magnetron sputtering was used for the deposition of a nanostructured thin film of Hydroxyapatite ceramic on the surface of stainless steel AISI 304. The RF sputtering process parameters (such as the RF-power and the deposition time in the deposition process) were characterized/optimized by Taguchi analysis, and evaluating the thin film phases and wear resistance, and the corrosion resistance was determined by electrochemical techniques. The scanning electron microscope (SEM) equipped with electron discharge microscopy, the atomic force microscope (AFM), X-ray diffraction, and optical microscopy were used to characterize the properties of the HAP thin-film coatings. The mechanical property and the tribological properties of the HAP coating were measured using Vickers hardness and, micro scratch tester. The electrochemical corrosion technique was used to analyze the corrosion behavior of the thin film. Whilst optimization of the process parameter was carried out using L9 Taguchi orthogonal array...
M.Ing. (Mechanical Engineering)