Author(s): |
Qiang Li, The Key Laboratory of New Materials in Automobile of Liaoning Province, Liaoning University of Technology, Jinzhou, China, 121001 Jing-yuan Yu, The Key Laboratory of New Materials in Automobile of Liaoning Province, Liaoning University of Technology, Jinzhou, China, 121001 Ping Shi, The Key Laboratory of New Materials in Automobile of Liaoning Province, Liaoning University of Technology, Jinzhou, China, 121001 Chun-wei Li, The Key Laboratory of New Materials in Automobile of Liaoning Province, Liaoning University of Technology, Jinzhou, China, 121001 Xu-dong Sun, School of Material & Metallurgy, Northeastern University, Shenyang, China, 110004 |
Abstract: |
Porous NiTi alloys prepared by combustion synthesis were modified using direct current-pulse anodic oxidation technology in low temperature and deposited with HA in simulated body fluid after anodic oxidation. The effect of pulse current on the process of anodic oxidation was analyzed. The morphology, phase composition, anti-corrosion behavior and Ni release of surface film of porous NiTi alloy after anodic oxidation and HA deposition were studied The results show uniform and porous oxidation film on the surface of porous NiTi alloy is obtained after anodic oxidation. After immersing in simulated body fluid for 15 days, the surface of the NiTi alloys with anodic oxidation is covered with a continuous HA layer about 480nm thick. The icorr density of porous NiTi alloy after surface modification decreases from 12.8μA/cm-2 to 0.12μA/cm-2, indicating their improved corrosion resistance after the chemical treatments. Due to the HA layer, Ni release can be significantly reduced, and biocompatibility of the porous NiTi alloys is improved.
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