| To solve the cost and property problems met in the clinical application of titanium matrix biomedical materials, a new set of fabrication technology has been designed and developed to reduce the production cost in this study, and a new type of K2Ti6O13 /Ti matrix biomedical material has been manufactured to improve the biomedical properties. Surface morphology, phase constitution, bonding strength, biocompatibility and bioactivity of the coating were analyzed and evaluated. The results indicate as follows:The critical partial pressures of oxygen and nitrogen are both functions of temperature. Oxygen and nitrogen partial pressures can be sufficiently lowered by pumping and argon inflating for many times. Oxygen and nitrogen contamination to titanium alloy is effectively avoided by three times of pump-inflation circulation with the argon inflation pressure of 104Pa. The designation and fabrication of CaO matrix coating of the crucible makes it possible to avoid the carbon contamination from graphite crucible. All above will create conditions for the biology application of the low cost titanium alloys.The K/T ratio and the culcination temperature are the principal factors to determine which kind of potassium titanate to form. Culcination temperature and time influence the self-generated oxide layer, and then act on the coating's quality and bonding strength. To establish the in situ KDC process, the influences of the K2CO3 liquid phase stroma, the same element-different structure transfermation of titanium, the self-generated oxide layer should be taken into consideration, and the culcination temperature and time should also match best. We can depict the synthesis process of K2Ti6O13 as a model of 'surround'-'counter-surround'. In this study, the coating gets the best quality at temperature of 1050Cculcinating for 0.5~1hour. The culcination product is mainly white spiny K2Ti6O13 crystal whisker whose diameter and length are 1 μm and 10μm respectively. The coating thickness is 6μm, and the surface roughness is 1.2μm~ 1.8μm. The suitable surface roughness provide advantages for ingrowth of bone. The bonding strength between coating and matrix is as high as 24MPa, which doubles the one of HA coating. Furthermore, the K2Ti6O13 coating can bear the cold-hot impact during air-cool process. The main reasons of the high bonding strength are as follows: the suitable match of expand coefficient, the participation to the synthetic reaction of the self-generated oxide layer, and anchor dropping effect. Friction wear experiment shows that the coating has good wear-resistance.After immersion in the simulate body fluid (SBF), a calcium-phosphorus layer, whose calcium-phosphorus scale is near to the human bone's, is formed on the coating. The calcium-phosphorus layer has porous reticulation structure, which is beneficial to the nourishment transmission, bone ingrowth and scrap excretion during the body metabolism. The honeycomb-like frame insures the bone certain strength. These above makes clear that K2Ti6On coating has good bioactivity.Haemocompatibility experiment finds that the blood clotting time of K2Ti6On/Ti matrix biomedical materials is much longer than that of Co-Cr alloy; and the platelet sticking number on K2Ti6O13/Ti alloy is obviously less than those on the Co-Cr alloy and 316L stainless steel. These indicate that the Haemocompatibility of K2Ti6O]3/Ti alloy is remarkably superior to the Co-Cr alloy and the 316L stainless steel.Cell cultivation experiment indicates that the cytodensity in the hole with K2Ti6O13/Ti matrix biomedical materials is as high as six times of the initial inoculation density after seven days of cultivation. The K2Ti6O13/Ti alloy has superior biocompatibility and bioactivity as compared with 316L stainless steel and Ti alloy without coating.
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