目的 提高304不锈钢的耐腐蚀性能.方法 采用磁控溅射技术在304不锈钢表面沉积TiN涂层,并采用SEM、XRD及GDOES对涂层的表面形貌、成分进行测试.通过极化曲线和电化学噪声技术评价TiN涂层和基体在pH=2.5的3.5%(质量分数)NaCl溶液中的腐蚀行为,并研究涂层的失效机制.结果 在304不锈钢表面沉积了厚约1μm且均匀、致密的TiN涂层.极化曲线分析表明,基体和TiN涂层试样出现了自钝化和点蚀现象,其中304不锈钢基体的腐蚀电位为-0.41 V,腐蚀电流密度为8.01×10-6 A/cm2,与之相比,TiN涂层的腐蚀电位(-0.28V)明显增大,腐蚀电流密度(6.34×10-8 A/cm2)显著降低.电化学噪声分析显示,在浸泡初期,TiN涂层电极电流暂态峰数量较少,强度较大,噪声电阻较低,而随着浸泡时间的延长,其电流暂态峰数量增加,强度降低,噪声电阻明显大于304不锈钢基体.腐蚀形貌观察表明,304不锈钢和TiN涂层表面均出现了点蚀.结论 TiN涂层能够明显改善基体的耐蚀性能.TiN涂层主要起物理阻碍作用,涂层的主要失效形式是涂层表面的微观缺陷和破裂.
Objective To improve the corrosion resistance of 304 stainless steel. Methods TiN coating was fabricated on the surface of 304 stainless steel by magnetron sputtering. The microstructure distribution and chemical composition of TiN coating were characterized by SEM, XRD and GDOES. The corrosion behavior of 304 stainless steel and TiN coatings in 3. 5 wt.% NaCl solu-tion (pH=2. 5) was discussed by polarization curves and electrochemical noise technique. The failure mechanisms of coating was studied according to the electrochemical noise signals, the noise resistance and corrosion morphology. Results The smooth and dense TiN coating with a thickness of about 1 μm was deposited on 304 stainless steel. Substrate and TiN coating showed passiva-tion and pitting in polarization curves, and the values of corrosion potential ( Ecor ) and corrosion current density ( Jcor ) of substrate were-0. 41 V and 8. 01×10-6 A/cm2, respectively. However, for TiN coating the value of Ecor (-0. 28 V)shifted toward the posi-tive, and the value of Jcor (6. 34×10-8 A/cm2) decreased sharply. All the results showed the TiN coating exhibited an excellent corrosion resistance. The results of electrochemical noise showed that the TiN coating revealed fewer transients, higher amplitude current transients and lower noise resistance ( Rn ) at beginning of the testing. However, with increasing immersion time the current transients of TiN coating showed a significant change, and the value of Rn had a sharp increase, compared with the substrate. The corrosion micrograph showed that the pitting occurred on the substrate and TiN coating. Conclusion TiN coating could obviously improve the corrosion resistance of 304 stainless steel. TiN coating acted as the physical barrier, and the corrosion resistance was mainly limited by the pinhole and break.
参考文献
[1] | Gupta, R. K.;Birbilis, N..The influence of nanocrystalline structure and processing route on corrosion of stainless steel: A review[J].Corrosion Science: The Journal on Environmental Degradation of Materials and its Control,2015Mar.(Mar.):1-15. |
[2] | Chen Pan;Li Liu;Ying Li;Fuhui Wang.Pitting corrosion of 304ss nanocrystalline thin film[J].Corrosion Science: The Journal on Environmental Degradation of Materials and its Control,2013Aug.(Aug.):32-43. |
[3] | Liu, T.;Zhang, F.;Xue, C.;Li, L.;Yin, Y..Structure stability and corrosion resistance of nano-TiO_2 coatings on aluminum in seawater by a vacuum dip-coating method[J].Surface & Coatings Technology,20107(7):2335-2339. |
[4] | 李瑛;屈力;王福会;邵忠宝.TiN涂层电化学腐蚀行为研究Ⅰ.TiN涂层的保护性能与失效机制[J].中国腐蚀与防护学报,2003(2):65-69. |
[5] | 张慧桥;黄晓波;田伟红;郭杨阳;李娟;范爱兰;唐宾.Ti6Al4V 表面 Ti-Cu-N 纳米薄膜溅射沉积及其抗菌性能研究[J].表面技术,2014(4):1-5. |
[6] | Fan-Yi Ouyang;Wei-Lun Tai.Enhanced corrosion resistance of TiN-coated stainless steels for the application in flexible dye-sensitized solar cells[J].Applied Surface Science: A Journal Devoted to the Properties of Interfaces in Relation to the Synthesis and Behaviour of Materials,2013Jul.1(Jul.1):563-570. |
[7] | B.P. Markhali;R. Naderi;M. Mahdavian;M. Sayebani;S.Y. Arman.Electrochemical impedance spectroscopy and electrochemical noise measurements as tools to evaluate corrosion inhibition of azole compounds on stainless steel in acidic media[J].Corrosion Science: The Journal on Environmental Degradation of Materials and its Control,2013Oct.(Oct.):269-279. |
[8] | The influence of the cathodic process on the interpretation of electrochemical noise signals arising from pitting corrosion of stainless steels[J].Corrosion Science: The Journal on Environmental Degradation of Materials and its Control,20104(4):1362. |
[9] | Bahrami, M. J.;Shahidi, M.;Hosseini, S. M. A..Comparison of electrochemical current noise signals arising from symmetrical and asymmetrical electrodes made of Al alloys at different pH values using statistical and wavelet analysis. Part I: Neutral and acidic solutions[J].Electrochimica Acta,2014:127-144. |
[10] | 张涛;杨延格;邵亚薇;孟国哲;王福会.电化学噪声分析方法的研究进展[J].中国腐蚀与防护学报,2014(1):1-18. |
[11] | 董泽华;郭兴蓬;郑家燊.电化学噪声的分析方法[J].材料保护,2001(7):20-23. |
[12] | 阮红梅;董泽华;石维;陈东初.基于电化学噪声研究缓蚀剂对AA6063铝合金点蚀的影响[J].物理化学学报,2012(9):2097-2107. |
[13] | A.M. Homborg;E.P.M. van Westing;T. Tinga;X. Zhang;P.J. Oonincx;G.M. Ferrari;J.H.W. de Wit;J.M.C. Mol.Novel time-frequency characterization of electrochemical noise data in corrosion studies using Hilbert spectra[J].Corrosion Science: The Journal on Environmental Degradation of Materials and its Control,2013Jan.(Jan.):97-110. |
[14] | A. M. Homborg;T. Tinga;X. Zhang;E. P. M. van Westing;P. J. Oonincx;G. M. Ferrari;J. H. W. de Wit;J. M. C. Mol.Transient analysis through Hilbert spectra of electrochemical noise signals for the identification of localized corrosion of stainless steel[J].Electrochimica Acta,2013:84-93. |
[15] | Tao Zhang;Yawei Shao;Guozhe Meng;Fuhui Wang.Electrochemical noise analysis of the corrosion of AZ91D magnesium alloy in alkaline chloride solution[J].Electrochimica Acta,20072(2):561-568. |
- 下载量()
- 访问量()
- 您的评分:
-
10%
-
20%
-
30%
-
40%
-
50%