DEVELOPMENT OF HYDROXY APATITE (HAP) COATiNG ON STAINLESS STEEL FROM SIMULATED BODY FLUID SOLUTION & ITS CHARACTERIZATION

Abstract

1-lydroxyapatite (HA,C34(PO4)6(OH)2) is an inorganic bioceramic compound which has attracted widespread interest in various biomedical applications like in dental and orthopedics due to its close similarities with bone and teeth of inorganic mineral component. However there is always concern about the corrosion and wear resistance of metallic bio-implants, in their bioaetivity. Ihus it becomes niandatory to improve the surface properties of metallic biomaterial like stainless steel in order to overcome the limitations, although being still widely used in orthopedic implant applications. In this work stioehiometric hydroxyapatite is synthesized using of diammonium hydrogen phosphate ((NI 14)2 IIPO.1) and calcium nitrate tetrahydrate (Ca(NO3)2.4H20). containing urea (I 12NC0N1-12) salts dissolved in simulated body fluid solution (5131:), at P11 of 7.4 and 37°C by using technique of a novel chemical precipitation because Hydroxyapatite (I IA) is a high temperature process its decomposed when heated above 1200°C in air. SBF had an excellent thermal stability even when heated at 1300°C in an air atmosphere. The product was sintered thrice at three different temperatures 400CC, 850°C arid 1300°C to improve its crystallinity. The final powder was characterized by Energy dispersive x—ray -. (EDAX) analysis is carried out to estimate the amount of calcium and phosphorous. Field Emission Scanning electron microscopy (FESEM) and X-ray diffraction (XRD). Hydroxyapatite coating was done by biomimetic method on stainless steel 316L. The stainless steel 316L sample dips in solution (before the filtration) and coming out from solution and then dried. This process is carried out again and again so finally a layer form on the sample and coating was characterized in detailed by image analyzer (Model Leica). Energy dispersive x— ray (EDAX) analysis. Field Emission Scanning electron microscopy (FESEM) analysis and Xray diffraction (XRD).