Composite layers on titanium and Ti6Al4V alloy for medical applications

Purpose: The paper presents the possibility of creating biomaterials through designing bioceramic composite layers on cpTi and Ti6Al4V alloy by hybrid method. TiN+Ti2N+áTi(N) and SiO2-TiO2 intermediate layer were produced by glow-discharge nitriding and sol-gel methods, respectively. Finally, hydroxyapatite nano-film deposited by electrophoresis. Design/methodology/approach: The composite bioceramic systems were characterized from the standpoint of microstructure and morphology analysis of surface layers. The study was performed by X-ray diffraction technique, IR-fourier transform, SEM, AFM and in SBF (bioactivity). Wear resistance in environmental conditions (laboratory air) and in simulated body fluid (SBF) were carried out by pin-on-disc method. Findings: The suggested innovative hybrid method allows the manufacture of the bioceramic composite layers with definite microstructure, phasic and chemical composition and surface topography. The intermediate layers are characterized by low thickness, good structural homogeneity, satisfying bonding with a metal substrate, whereas, external hydroxyapatite layer is very thin, homogenous, bioactive and durable. Research limitations/implications: It seems necessary to conduct further investigation in the field of adhesion of composite systems and, particularly, biological study of capabilities of bone tissue and bacteriological behaviour in the environment of implant with studied layers. Practical implications: The high layer quality, bioactivity and possibility of improving the mechanical properties of hydroxyapatite, it is advantageous to produce composite systems with TiN+Ti2N+áTi and SiO2-TiO2 intermediate layers. Originality/value: The modification of the surface of metal substrate, produced by the hybrid method, may be an effective way to form a new generation of titanium biomaterials.