Biomedical ECAP Pure Ti Mechanical Properties And Surface Activity

With the development of medical technology, the application of commercial pure titaniumincreases very fast. Compared with other structural materials, pure titanium has a goodbiocompatibility, especially it does not contain toxic elements. Therefor, in recent years, pure titaniumhas got much more attentions of scholars in our country and abroad. However, Pure titanium-used asa biomedical implant material, its low strength and low fatigue strength, which inhibit the applicationof pure titanium in the field. So, it is important to improve the property of pure titanium by a processof processing method. ECAP (Equal channel angular pressing) uses the method of cutting materialorganization to get the grain refinement, in this way the properties of the materials in significantlyimproved. In these decades, by the ECAP method to improve the performance of titanium isbecoming increasingly more and more widespread used.In this paper, self-designed mold and heat insulation device have been successfully designed andcarried out. With BC path, at410℃temperature and with1mm/min extrusion speed, we ECAPed thetantinium sample and got the refined micro organization materal. Then we studied the changes of themechanical property、the fatigue resistance and the surface activity.Based on the samples of coarse grain、ECAPed one pass and ECAPed two pass, we developed aseries of experiments: Optical microscope test、Hardness test、Tensile test、Fatigue test and surfaceactivity test. The results show that with the2passes ECAP process, the grain size of CP-Ti is small.The coarse equiaxed grain microstructure is developed into elongated grain, twin, band microstructure.With the increase of the ECAP pass, the interspace between the bands is finer. With the ECAPprocess, the strength of CP-Ti is improved to1240MPa, the Vickness hardness is improved to Hv319and the elongation is decreased to16.7%. The fatigue strength is improved from220MPa to280MPa,by27.3%. The surface active in artificial body fluid is getting better with the number of passesincreased. Besides, after two passes of ECAP, pure Ti’s biological activity is significantly improved.