Study on Preparation and Properties of Magnesium and Titanium Based New Biocoatings with Ultrasonic Auxiliary Micro-arc Oxidation
|Course||Materials Processing Engineering|
|Keywords||Micro-arc oxidation Ultrasonic wave Magnesium alloy Titanium alloy Additive|
Magnesium alloy to improve the corrosion resistance of titanium alloy bioactive and slow bone repair, using ultrasonic assisted micro-arc oxidation process, according to the essential element content security value in human bone, calcium, phosphorus element basis. electrolyte system were added to the appropriate AgNO3 La (NO3) 3, NaF and Na2SiO3 as an additive, magnesium and titanium alloy surface bio-modification, preparation of wear-resistant, corrosion resistant and antibacterial properties of magnesium-based, titanium-based bone repair porous the new bioactive coating material. SEM, AFM, EDAX, XRD, HRTEM Technical Analysis coating microstructure and organizational structure, research ultrasound-assisted micro-arc oxidation coating formation mechanism, Determination of coating thickness, surface porosity, bond strength, antibacterial properties and in the human body simulation The friction and wear and corrosion resistance of the body fluids. The results show that: the ultrasound-assisted micro-arc oxidation technology to prepare the biological coating consists of a dense layer and a porous surface layer composition, the introduction of ultrasonic waves to improve the cationic deposition amount of the biological coating of micro-arc oxidation, the thickness uniformity of the distribution and the bonding strength; coating The formation mechanism for the growth of early DPRK within the matrix, after the gradual growth toward the outside of the matrix elements into the coating mechanism of diffusion and electrophoresis; AgNO3, La (NO3) 3, NaF and Na2SiO3 additives added to increase the coating surface elements deposited amount and the type of coating thickness and porosity. The new magnesium group, with a titanium-based biological coating thickness of approximately 16μm to 30 μm, 76μm ~ 90μm, the porosity was approximately 26%, and 23%, respectively, mainly by the three-dimensional island structures 10nm to 67 nm particle size of the nano-sized periclase Ag2O, the biological activity of stone type MgO, 2.5nm to 15 nm particle size of the nanoscale anatase and rutile TiO2 crystal state particulate composition, wherein the magnesium-containing silver biological coating also has antibacterial effect Ca9MgNa (PO4) 7 The crystal produced, the titanium-containing silver biological coating also has antibacterial action of Ag2O crystal produced, indicating a type of coating having a superior biological activity and antimicrobial. Compared with the single calcium, phosphorus biological coating additives content, drawn by the tensile test magnesium the base load fluoride coating bond strength of 3.47MPa to 10.00 MPa, titanium matrix containing silver contained lanthanum, and upload silicon coating respectively 1.97MPa to 16.49MPa 2.93MPa ~ 14.00MPa has a good combination of strength and 6.71MPa ~ 8.92MPa, reflects the substrate and coating; magnesium base containing silver, drawn by the friction and wear experiments contained fluorine and upload silicon coated the coefficient of friction layer in the human body in simulated body fluid (SBF) were reduced from 0.18 to 0.32,0.17 to 0.35 and 0.19 to 0.31, titanium matrix containing silver contained lanthanum upload silicon coating were reduced by 0.16 ~ 0.48,0.41 ~ 0.52 0.13 to 0.48, the material reflects the excellent wear resistance, friction and wear mechanisms in SBF mainly abrasive wear and adhesive wear; containing silver magnesium based on electrochemical corrosion experiments contained fluorine carrier silicon coating in SBF in the corrosion potential is increased by a 11 mV to 102mV 95mV ~ 170mV, with 18mV ~~ 138mV, about one to two orders of magnitude lower corrosion current titanium matrix containing silver contained lanthanum carrier silicon coating the corrosion potential increased 15mV ~ 47mV, 94mV ~ 163mV with 57mV ~ 136mV, about one to two orders of magnitude lower corrosion current material reflects the excellent corrosion resistance, corrosion mechanism in human SBF point corrosion; magnesium matrix containing silver contained fluoride and titanium silver base load carrier lanthanum coating antibacterial rate of 90% to 96%, from 61% to 76%, 61% to 92% and 50% to 68%, respectively, indicating that such material in bone tissue healing process has anti-inflammatory bactericidal effect.