| It is very important to improve the surface characteristics of titanium alloy (Ti6A14V) for developing medical treatment appliance as artificial bone, such as artificial joints* artificial root of tooth and artificial bone, etc. The related research area is one of the front edges of biomedicine material research at present. In this thesis, the research about surface modification of titanium alloy was carried on starting with improving stability of calcium phosphate biomedical coating by force of chemical treatment, Physical Vapor Deposition(PVD) of titanium metal at high temperature and Electrophoresis Codeposition(EPCD) and sintering technology of the coating. By way of the studying of graded design of microstructure and composition of coating and EPCD and sintering technology, a systemic technology by which a calcium phosphate graded ceramic coating was prepared and sintered rapidly on the surface of a complex shaped product was obtained and a high function titanium alloy/bioglass(BG)/hydroxyapatite(HA)graded coating was developed. The technology is low costing, no pollution and friendly to environment, which will extend the application area of calcium phosphate biomedical coating and lengthen its life span of usage.Treat the surface of titanium alloy with acid and base, nitric acid and sodium hydroxide respectively, measure composition of the corrode products using Plasma Emission Spectrum and observe surface morphology of the corroded titanium alloy with SEM, the results showed that a homogenization corrosion occurred while nitric acid was used, so a selective dissolution for element V and Al on the surface of titanium alloy could not be achieved, but sodium hydroxide could do and leave Ti element in gel state TiO^ on the surface of titanium alloy. The gel TiO2 not only has good biocompatibility, but also can induce deposition of calcium phosphate minerals and is beneficial to the banding of biogas with the titanium ally surface, so the base processing method is expected to be a good pretreatment method of titanium alloy surface for biomedical coating.In order to improve biocompatibility of titanium alloy surface the PVD of pure metal Tion the titanium alloy surface in vacuum and at high temperature was studied. After the PVD the variation of elements content and distribution on the surface and cross section of titanium alloy were analyzed using Scanning Electron Microscope (SEM) and Electron Probe X-ray Fluorescence Micro area AnalysisC EPMA), the results showed that a Ti coating in thickness of 20 u m, containing richly element V, formed on T16A14V alloy surface after the evaporating and condensing at 1000癈for 2~4 hours, and grains in the alloy could grew up rapidly during the heat treatment, which will cut down mechanics behavior of the titanium alloy, and a segregation phenomenon of element V near the titanium alloy surface occurred. For element Al there only existed diffusing transfer causing by concentration difference. Therefore, the heat treatment of T16A14V alloy should be carried out at lower temperature that is under its phase shift point.Through designing of composition and structure of the bioactive graded coating, innerstress and its distribution in the coating were analyzed and calculated, the results showed that when composition distribution coefficient n was 1.5, a reasonable stress distribution could be got, that was at the beginning of deposition the suspension containing richly BG granules was used so that a rich BG granules layer, a good transitional layer between BG layer at the bottom and the coating could be obtained at the titanium alloy side, the bottom of the coating; the stress value near the interface and surface and its character, pressure stress or tensile stress, were decided by the character of its composition itself. Changing composition distribution coefficient n could only change the variation tendency of stress in the coating, but did not change the stress distribution rule in the coating. The thinner the coating is, the sharper stress variation in the coa...
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