Experimental Study On Microstructure,Mechanical Properties And Corrosion Resistance Of Ti-Cu Sintered Alloy

Titanium alloys have been widely used in biomedical field because of its advantages of high specific strength,good biocompatibility,excellent corrosion resistance and so on.In our previous studies,it has been found that the sintered Ti-5Cu and Ti-10Cu alloys decreased the plasticity of materials due to the porosity and other defects formed during the sintering process.In this paper,Ti-Cu sintered alloys were subjected to extrusion processing in order to improve the comprehensive property.The effects of the Cu content and the processing way on the corrosion property,mechanical property and wear property were investigated by electrochemical measurrement,mechanical properties testing and friction and wear testing.machine.The wear behavior of the alloys under simulated body fluid was also tested on the friction and wear tester with electrochemical workstation.Antibacterial properties of the alloys were assessed by a plate-count method.The results are summaried as follows:Microstructure observation results showed that the Ti-5Cuand Ti-10Cu sintered alloys were composed of Cu-rich phase and ?-Ti,as well aslocally distributed Ti2Cu phase.The extrusion process did not change the phase constitute but refined the grain size and Ti2Cu particle significantly.Extrued Ti-Cu alloys exhibited higher hardness and compressive yield strength than Ti-Cu sintered alloys due to the fine grain and Ti2Cu particles.With the consideration of the total compressive strain,it was suggested that the extrusion process could improve the ductility of Ti-Cu alloy(S)alloys.The results of electrochemical experiments showed that the corrosion resistance of the alloy after extrusion treatment was improved.With the increase of copper content,the corrosion resistance of the alloy increased.Alloy showed different corrosion resistance in different solutions and the corrosion resistance was in the order of from high to low:Hank's,Saliva,Saliva-pH3.5 and Saliva+0.2F.Corrosion wear results showed that the alloy exhibited different wear resistance in four kinds of solution in the order from low to high of Hank's,Saliva,Saliva-pH3.5 and Saliva+0.2F solution.Compared with the dry frictionresult,the wear rate of the alloy in solution was significantly reduced,which showed that the lubrication and cooling effects of the solution were significant.Compared with the result of the static corrosion,friction accelerated corrosion.Antibacterial experimental results indicated extrusion treatment did not affect the antibacterial properties of sintered titanium copper alloy,and both the extruded and sintered titanium copper alloys exhibitedstrong antibacterial properties.