Experimental Research On Effect Of Surface Treatment On The Corrosion And Antibacterial Properties Of Antibacterial Ti-Cu Alloy

Due to the excellent mechanical properties,good corrosion resistance and biological compatibility,Titanium and titanium alloy were widely used in artificial joint,dental implant,bone screws and so on.However,the biological corrosion and infection caused by the implanted microbes are great challenge in the medical field at the present stage.Ti-Cu alloy has a very good antibacteria properties,which can prevent biological corrosion and infection effectively,while the biological activity of titanium alloy is not satisfying without surface activation.So it is still a difficult issue that how to make Ti-Cu alloy possess a good anti-bacteria as well as biological activity.Firstly,this thesis researches the surface physical,chemical,corrosion resistance properties of Ti-3Cu alloy in bacteria suspension after heat-treatment,Then the corrosion behavior,anti-bacteria and anti-adhesion properties of Ti-3Cu alloy were analyzed after sandblasted,large-grit,acid-etched(SLA)treatment;alkali heat treatment and laser treatment.In order to study the surface physical,chemical,anti-bacterial and corrosion properties in bacteria suspension after heat-treatment and surface treatment process.Scanning electron microscopy(SEM),confocal laser scanning microscope(CLSM),X-ray diffraction(XRD),X-ray Photoelectron Spectroscopy(XPS),contact angle measurement,electrochemical workstation and antibacterial experiment were used in this thesisCLSM and surface contact angle results show that heat treatment can not able to change the surface morphology,roughness and contact angle,but the SLA,alkali heat treatment and laser treatment can improve the surface roughness and reduce surface contact angle,Thus surface treatment process improve the hydrophilic.XRD observation shows that after heat treatment,Ti-3Cu mainly consist of ?-Ti and Ti2Cu phase.Compared with forged Ti-3Cu,the amount of Ti2Cu phase was dissolved in matrix after solid treatment,while after aging treatment,the amount of surface Ti2Cu phase increased significantly.Through SLA,alkali heat and laser surface modify process,the mainly contents of surface are still ?-Ti and Ti2Cu phase.After alkali heat treatment,the surface formed a sodium titanate gel layer,the result of XPS shows that Ti and Cu elements were mainly existed as TiO2 and CuO,Ti and Cu valence state corresponding to+2.The bacterial electrochemistry experiment shows that aging treated Ti-3Cu alloy has an excellent anti-corrosion property.Through the observation of SEM,The bacterial cannot adhere to the surface of aging treated Ti-3Cu alloy,Ti2Cu phase enriched in the surface,which has a strong anti-adhesion property.Besides,SLA,alkali heat and laser surface treatment process can further improve the corrosion resistance in bacteria suspension.The antibacterial experimental results show that SLA,laser and alkali surface modify still have antibacterial property,The antibacterial rates of SLA,alkali heat and laser surface treatment process are 73%,71%and 55%,individually.