氮化钛镀膜后纯钛在不同氟浓度中的耐腐蚀性能研究

Effects of TiN coating on corrosion resistance of casted titanium

目的:观察纯钛表面镀制氮化钛薄膜后在不同氟质量浓度人工唾液中的耐腐蚀性。方法:用动电位极化技术测试对照组和镀膜组纯钛在氟质量浓度为0、500、2000mg/L的人工唾液中的自腐蚀电流密度和自腐蚀电位,扫描电镜观察实验面的表面形貌,对结果进行比较分析。结果:对照组和镀膜组纯钛在三种氟质量浓度中的自腐蚀电流密度分别为1.53±0.23、2.29±0.21、4.13±0.19和0.26±0.01、0.32±0.01、0.66±0.03μA,自腐蚀电位分别为-0.93±0.07、-0.89±0.11、-0.57±0.05和-0.54±0.02、-0.56±0.03、-0.50±0.03V。随氟质量浓度的增加对照组和镀膜组纯钛的自腐蚀电流密度逐渐增大,而镀膜后纯钛的自腐蚀电流密度较未镀膜组明显减小(P<0.01)。扫描电镜显示,随氟质量浓度的增加对照组和镀膜组纯钛的表面腐蚀逐渐加重,而镀膜后纯钛较对照组纯钛的表面腐蚀形貌明显减轻。结论:不断增加的氟浓度使对照组和镀膜组的耐腐蚀性逐渐下降,而脉冲电弧离子镀氮化钛薄膜使纯钛的耐腐蚀性增强。

Objective： To investigate the effects of TiN film by pulsed bias arc ion plating technique on the corrosion resistance of pure titanium in the artificial saliva with different fluoride concentrations. Methods： Potentiodynamic polarization technique was used to measure the current density of corrosion（Icorr） and the electric potential of corrosion（Ecorr） of untreated and TiN-coated pure titaniums in the artificial saliva with the concentrations of 0,500,2000 mg/L fluoride.After the electrochemical experiment, the microstructure was observed by scanning electron microscope（SEM）.Results： The values of Icorrs of untreated and TiN-coated titanium were 1.53 ±0.23, 2.29 ±0.21, 4.13 ±0.19 and0.26±0.01,0.32±0.01,0.66±0.03 μA in different fluoride concentrations, respectively.The values of Ecorrs were- 0.93±0.07,- 0.89±0.11,- 0.57±0.05 and- 0.54±0.02,- 0.56±0.03,0.50±0.03 V respectively.The Icorrs of TiN-coated group were significantly lower than that of control group（P 〈0.01）.The Icorrs significantly increased with the increasing of fluoride concentrations（P〈 0.01）.The Ecorrs of TiN-coated were significantly higher than that of control group（P 〈0.01）. The observation of SEM showed that the microstructure in the pure titanium after corrosion was much severely than that in TiN-coated titanium.The surfaces of pure titanium were damaged by corrosion with increasing of fluoride concentrations. Conclusion： The increase of fluoride concentrations could weaken the corrosion resistance of both untreated and TiN-coated pure titanium, but pulsed bias arc ion plated TiN coating might significantly increase the corrosion resistance of pure titanium.