- Email: [email protected]
Enhancing general corrosion resistance of biomedical high nitrogen nickel-free stainless steel by water treatment
Materials Letters 251 (2019) 196–200
Contents lists available at ScienceDirect
Materials Letters journal homepage: www.elsevier.com/locate/mlblue
Enhancing general corrosion resistance of biomedical high nitrogen nickel-free stainless steel by water treatment Yixun Yang a,b, Qingchuan Wang a,⇑, Jun Li a,b, Lili Tan a, Ke Yang a a b
Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China School of Materials Science and Engineering, University of Science and Technology of China, Shengyang 110016, China
a r t i c l e
i n f o
Article history: Received 13 February 2019 Received in revised form 25 April 2019 Accepted 18 May 2019 Available online 20 May 2019 Keywords: Biomaterials Stainless steels Water treatment Corrosion Chromium enrichment
a b s t r a c t An extremely simple and environmentally friendly water treatment was developed to enhance the general corrosion resistance of biomedical high nitrogen nickel-free stainless steels (HNNFS). After treatment, the corrosion rate of HNNFS could dramatically reduce to 1/20 of the untreated in 37 °C 0.9 wt% NaCl solutions. Then the passive film on HNNFS was analyzed by electrochemical impedance spectroscopy (EIS) and X-ray photoelectron spectroscopy (XPS). It was found that Cr enrichment and thickness increase of passive film contributed to the improvement of general corrosion resistance of HNNFS. Ó 2019 Elsevier B.V. All rights reserved.
1. Introduction With an excellent comprehensive performance, metallic materials are widely used in clinical applications. General corrosion of metals cannot be avoided in human body. Previous studies indicate that ions released from metallic implants have strong effects on their biocompatibility, and some inflammatory responses are closely related with the excess dissolution of toxic ions [1]. In this case, studies need to be performed on biomedical metals to reduce their ions dissolution. With excellent mechanical properties and pitting corrosion resistance, high nitrogen nickel-free stainless steels (HNNFS) have attracted considerable attention [2–4]. Compared with traditional stainless steels, HNNFS acquire excellent biocompatibility [5] because they could avoid the harmful effects of nickel in human body, such as sensibilization and teratogenesis [6]. And the problem of in-stent restenosis caused by Ni could be solved by nitrogen alloying [7]. However, to increase N content, a large amount of Mn is added in HNNFS, and it strongly weakens the general corrosion resistance of stainless steels [8]. This behavior of HNNFS would affect their biocompatibility. The excess dissolution of Mn would induce ‘‘Manganism”, which is a neurological disorder similar to
⇑ Corresponding author. E-mail address: [email protected] (Q. Wang). https://doi.org/10.1016/j.matlet.2019.05.081 0167-577X/Ó 2019 Elsevier B.V. All rights reserved.
Parkinson’s disease [1]. In order to improve biocompatibility, it is important to enhance the general corrosion resistance of HNNFS. However, until now no research has been performed to solve this problem. Nowadays, nitric acid passivation is widely used to improve corrosion resistance of stainless steels. But acid passivation is not environmental-friendly, and lots of additional costs are needed to treat the acid waste. In this study, we try to develop a simple and environmental-friendly water treatment to enhance the general corrosion resistance of HNNFS. Electrochemical impedance spectroscopy (EIS) and X-ray photoelectron spectroscopy (XPS) analyses were performed to elucidate the corrosion resistance mechanisms of this treatment. 2. Materials and methods 2.1. Materials and samples preparation Chemical compositions of experimental HNNFS are as follows (wt.%): N 0.92, Cr 18.30, Mn 14.90, Mo 2.60, Si 0.31, S 0.0094, P 0.010, C < 0.02 and Fe balance. 316L stainless steel was chosen as control material (wt.%): Cr 17.2, Mn 1.28, Mo 2.16, Ni 14.60, Si 0.24, C 0.03 and Fe balance. The plates of both materials were solution treated at 1150 °C for 1 h followed by water quenching to ensure fully austenite. All samples preparation methods were the same as our previous research [3].
Y. Yang et al. / Materials Letters 251 (2019) 196–200
2.2. Experimental methods Water treatments with various temperature and time were investigated. Samples were treated in pure water for 60 min at different temperature (25 °C, 50 °C, 75 °C and 95 °C) and at 95 °C for different time (10 min, 60 min, 300 min and 600 min). As contrast, samples of HNNFS and 316L were treated with common passivation process in 25 wt% nitric acid solution at 25 °C for 1 h [9], and untreated samples were only exposed in air for more than 2 days. Potentiodynamic tests and EIS were performed in 0.9 wt% NaCl solution at 37 °C using Gamry Reference 600. Potentiodynamic tests were performed at a scan rate of 0.1667 mV/s. EIS was conducted at open circuit potential using a frequency range from 100 kHz to10 mHz with a 10 mV potential amplitude. According to the ISO 10993–15:2000 standard, immersion test was performed in 0.9 wt% NaCl solution at 37 °C for 7 days with 0.8 mL/ cm2 immersion ratio. Ions releasing concentration of samples was measured by atomic absorption spectroscopy (AAS) Z000. Passive film was analyzed by XPS using the Al Ka X-ray source. 3. Results and discussion Fig. 1a and b show the effects of temperature and time of water treatment on polarization curves and self-corrosion current density (Icorr). Icorr was obtained by fitting the Tafel regions. With increase of temperature and time, Icorr obviously decrease. In addition, no obvious changes were observed on pitting potential after treatment. Fig. 1c and d show the ions releasing concentration of HNNFS after water treatment, and Fig. 1e presents the comparison of ions releasing concentration of HNNFS and 316L stainless steel before and after treatment with nitric acid. As Fe and Mn are main
197
releasing ions, ions releasing concentration of HNNFS only includes these two ions. For 316L, Ni ions are also included. Fig. 1e shows that the general corrosion resistance of HNNFS is much weaker than that of 316L. In Fig. 1c and d, a sharp reduction of ions releasing concentration is observed with increasing temperature and time of water treatment. It is worth noting that, when treatment time is 600 min, the ions releasing concentration could decrease to 1/20 of untreated samples. That means the corrosion rate of water treated HNNFS could dramatically reduce to 1/20 of the untreated. Besides, Fig. 1e indicates that the general corrosion resistance of water treated HNNFS could be much better than that of 316L and HNNFS passivated by common nitric acid treatment. Therefore, this simple water treatment could significantly improve the general corrosion resistance of HNNFS. Similarly, water treatment has been successfully used to enhance the pitting corrosion resistance of 316L stainless steel [10]. To explore the quality and thickness of passive film, EIS analysis was conducted, and EIS results are showed in Fig. 2. The equivalent electrical circuit is also shown in Fig. 2, which refers to previous paper [11]. It includes solution resistance Rs, passive film resistance R1, passive film capacitance C, charge transfer resistance R2 and double-layer capacitance Q. Due to that the passive film is related to R1 and C1, only fitting data of R1 and C1 are listed in Table 1. As temperature and time increase, R1 gradually increases, which indicates that passive film quality becomes higher [11]. In addition, previous research shows that passive film thickness is inversely proportional to passive film capacitance [12]. Thus, the decrease of C1 indicates that passive film thickens as temperature and time increase. Those results further support the results from polarization curves and immersion test.
Fig. 1. Effects of temperature and time of water treatment on polarization curves, self-corrosion current (a and b) and ions releasing concentration (c and d); HNNFS and 316LSS before and after treatment by nitric acid (e); the error bars are total error.
198
Y. Yang et al. / Materials Letters 251 (2019) 196–200
Fig. 2. Effects of temperature (a and c) and time (b and d) of treatment on electrochemical impedance spectra; equivalent circuit for EIS.
Table 1 Passive film resistance and capacitance based on the equivalent circuit. R1 (105 X cm 25 °C 50 °C 75 °C 95 °C 10 min 60 min 300 min 600 min
3.41 ± 1.01 8.59 ± 2.57 13.50 ± 0.62 14.00 ± 3.66 8.47 ± 2.80 14.00 ± 3.66 14.10 ± 2.52 25.20 ± 5.47
2
)
C1 (10
5
F cm
2
)
6.33 ± 1.40 4.01 ± 0.38 3.57 ± 0.24 3.20 ± 3.81 4.96 ± 1.42 3.20 ± 0.38 3.11 ± 0.42 2.90 ± 0.31
In order to explore thickness and composition of passive film, XPS analysis is conducted. Fig. 3a shows the depth distribution of oxygen on temperature and time. Passive film thickness was determined by the oxygen content decreases to half of that at the surface. Hence, passive film thickness is 2–3 nm, and it thickens with increase of temperature and time. The variation trend of passive film thickness is consistent with EIS results. Fig. 3b presents that the Cr/Fe ratio in passive film increase with temperature and time. Those results indicate that temperature and time of water treatment facilitate Cr enrichment in passive film. According to the potential-pH diagram [13], during water treatment, the Cr oxide could stably exist in passive film, while Fe and Mn would dis-
solute as Fe and Mn ions. Hence, the Cr enrichment in passive film should be caused by the selective dissolution of Fe and Mn during water treatment [14]. Besides, compared with traditional stainless steel, weak general corrosion resistance of HNNFS could decrease the difficulty of Cr enrichment by water treatment. As shown in Fig. 3, the Cr 2p3/2 spectrums of all samples consist of three peaks including metallic Cr, Cr2O3 and Cr(OH)3. And the passive film formed at 95 °C contains more Cr2O3 and less metallic Cr than that formed at 25 °C. According to point defect model, the oxide film of stainless steels grows and thickens by diffusion of metal ions and oxygen [14]. At the passivation state, the diffusion process of oxygen becomes a controlling factor [15]. For HNNFS, oxygen atoms diffuse inward and react with Cr atoms to form Cr2O3. In this case, high temperature could promote the oxygen diffusion and form more Cr2O3 [16]. This should be the reason for temperature increase to enhance the general corrosion of HNNFS. Similarly, both Cr and oxygen contents are greatly increased in passive film as the extension of time, as shown in Fig. 3a and b. But Cr2O3 just slightly increases, while metallic Cr significantly increases. This is different with acid treatment. Study shows that, with treatment time increase, Cr2O3 greatly increased in passive film of stainless steel after HNO3 treatment [17]. For water treatment, dissolved oxygen in water is the oxidant. Although dissolved oxygen does not have strong oxidation ability as nitric acid, water
Y. Yang et al. / Materials Letters 251 (2019) 196–200
199
Fig. 3. Depth distribution of O (a) and Cr/Fe ration (b) at different temperature and time, XPS spectrum of Cr in passive film after treatment for 25 °C (c), 95 °C (d), 10 min (e) and 600 min (f).
treatment could concentrate more metallic Cr in passive film. By self-passivation, these Cr could react with dissolved oxygen and form more Cr2O3. Thus, the passive film on HNNFS could become more protective. Hence, water treatment could successfully enhance the general corrosion resistance of HNNFS.
to 1/20 of the untreated HNNFS and 1/3 of 316L stainless steel after common HNO3 treatment. Cr enrichment and thickness increase of passive film contributed to the improvement of general corrosion resistance of HNNFS. Declaration of Competing Interest
4. Conclusions In summary, a simple water treatment was successfully developed to enhance the general corrosion resistance of HNNFS. After treatment, the corrosion rate of HNNFS could dramatically reduce
We confirm that all the authors have checked the manuscript and have agreed to the submission and there is no financial interest to report. We certify that the submission is original work and is not under review at any other publication. If this manuscript can be
200
Y. Yang et al. / Materials Letters 251 (2019) 196–200
accepted, it will not be published elsewhere in the same form, in English or in any other language, without the written consent of the copyright-holder. Acknowledgment This work was supported by the National Natural Science Foundation of China [grant number 51801220]. References [1] [2] [3] [4]
Q.Z. Chen, G.A. Thouas, Mater. Sci. Eng. R 87 (2015) 1–57. M. Talha, C.K. Behera, O.P. Sinha, Mater. Sci. Eng. C 33 (2013) 3563–3575. Q.C. Wang, B.C. Zhang, Y.B. Ren, Corros. Sci. 145 (2018) 55–66. Q.C. Wang, B.C. Zhang, Y.B. Ren, Corros. Sci. 123 (2017) 351–355.
[5] R.F.V.V. Jaimes, M.L.C.D.A. Afonso, S.O. Rogero, Mater. Lett. 64 (2010) 1476– 1479. [6] Y.B. Ren, K. Yang, B.C. Zhang, Mater. Lett. 59 (2005) 1785–1789. [7] R. Köster, M. Sommerauer, J. Kähler, Lancet 356 (2000) 1895–1897. [8] M. Kemp, A.V. Bennekom, F.P.A. Robinson, Mater. Sci. Eng. A 199 (1995) 183– 194. [9] J.S. Noh, N.J. Laycock, W. Gao, D.B. Wells, Corros. Sci. 42 (2000) 2069–2084. [10] P.E. Klages, Z. Bai, M. Lobban, Electrochem. Commun. 15 (2012) 54–58. [11] G. Rondelli, P. Torricelli, M. Fini, Biomaterials 26 (2005) 739–744. [12] D. Wallindser, J. Pan, C. Leygrafa, Corros. Sci. 41 (1999) 275–289. [13] M. Pourbaix, Lectures on Electrochemical Corrosion, 1st ed., Plenum Press, New York. [14] C.-O.A. Olsson, D. Landolt, Electrochim. Acta 48 (2003) 1093–1104. [15] D.D. Macdonald, Electrochim. Acta 56 (2011) 1761–1772. [16] A.J. Bard, L.R. Faulkner, Electrochemical Methods Fundamentals and Application, 2nd ed., Wiley, New York. [17] J. Liu, T. Zhang, G.Z. Meng, Corros. Sci. 91 (2015) 232–244.
Contents lists available at ScienceDirect
Materials Letters journal homepage: www.elsevier.com/locate/mlblue
Enhancing general corrosion resistance of biomedical high nitrogen nickel-free stainless steel by water treatment Yixun Yang a,b, Qingchuan Wang a,⇑, Jun Li a,b, Lili Tan a, Ke Yang a a b
Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China School of Materials Science and Engineering, University of Science and Technology of China, Shengyang 110016, China
a r t i c l e
i n f o
Article history: Received 13 February 2019 Received in revised form 25 April 2019 Accepted 18 May 2019 Available online 20 May 2019 Keywords: Biomaterials Stainless steels Water treatment Corrosion Chromium enrichment
a b s t r a c t An extremely simple and environmentally friendly water treatment was developed to enhance the general corrosion resistance of biomedical high nitrogen nickel-free stainless steels (HNNFS). After treatment, the corrosion rate of HNNFS could dramatically reduce to 1/20 of the untreated in 37 °C 0.9 wt% NaCl solutions. Then the passive film on HNNFS was analyzed by electrochemical impedance spectroscopy (EIS) and X-ray photoelectron spectroscopy (XPS). It was found that Cr enrichment and thickness increase of passive film contributed to the improvement of general corrosion resistance of HNNFS. Ó 2019 Elsevier B.V. All rights reserved.
1. Introduction With an excellent comprehensive performance, metallic materials are widely used in clinical applications. General corrosion of metals cannot be avoided in human body. Previous studies indicate that ions released from metallic implants have strong effects on their biocompatibility, and some inflammatory responses are closely related with the excess dissolution of toxic ions [1]. In this case, studies need to be performed on biomedical metals to reduce their ions dissolution. With excellent mechanical properties and pitting corrosion resistance, high nitrogen nickel-free stainless steels (HNNFS) have attracted considerable attention [2–4]. Compared with traditional stainless steels, HNNFS acquire excellent biocompatibility [5] because they could avoid the harmful effects of nickel in human body, such as sensibilization and teratogenesis [6]. And the problem of in-stent restenosis caused by Ni could be solved by nitrogen alloying [7]. However, to increase N content, a large amount of Mn is added in HNNFS, and it strongly weakens the general corrosion resistance of stainless steels [8]. This behavior of HNNFS would affect their biocompatibility. The excess dissolution of Mn would induce ‘‘Manganism”, which is a neurological disorder similar to
⇑ Corresponding author. E-mail address: [email protected] (Q. Wang). https://doi.org/10.1016/j.matlet.2019.05.081 0167-577X/Ó 2019 Elsevier B.V. All rights reserved.
Parkinson’s disease [1]. In order to improve biocompatibility, it is important to enhance the general corrosion resistance of HNNFS. However, until now no research has been performed to solve this problem. Nowadays, nitric acid passivation is widely used to improve corrosion resistance of stainless steels. But acid passivation is not environmental-friendly, and lots of additional costs are needed to treat the acid waste. In this study, we try to develop a simple and environmental-friendly water treatment to enhance the general corrosion resistance of HNNFS. Electrochemical impedance spectroscopy (EIS) and X-ray photoelectron spectroscopy (XPS) analyses were performed to elucidate the corrosion resistance mechanisms of this treatment. 2. Materials and methods 2.1. Materials and samples preparation Chemical compositions of experimental HNNFS are as follows (wt.%): N 0.92, Cr 18.30, Mn 14.90, Mo 2.60, Si 0.31, S 0.0094, P 0.010, C < 0.02 and Fe balance. 316L stainless steel was chosen as control material (wt.%): Cr 17.2, Mn 1.28, Mo 2.16, Ni 14.60, Si 0.24, C 0.03 and Fe balance. The plates of both materials were solution treated at 1150 °C for 1 h followed by water quenching to ensure fully austenite. All samples preparation methods were the same as our previous research [3].
Y. Yang et al. / Materials Letters 251 (2019) 196–200
2.2. Experimental methods Water treatments with various temperature and time were investigated. Samples were treated in pure water for 60 min at different temperature (25 °C, 50 °C, 75 °C and 95 °C) and at 95 °C for different time (10 min, 60 min, 300 min and 600 min). As contrast, samples of HNNFS and 316L were treated with common passivation process in 25 wt% nitric acid solution at 25 °C for 1 h [9], and untreated samples were only exposed in air for more than 2 days. Potentiodynamic tests and EIS were performed in 0.9 wt% NaCl solution at 37 °C using Gamry Reference 600. Potentiodynamic tests were performed at a scan rate of 0.1667 mV/s. EIS was conducted at open circuit potential using a frequency range from 100 kHz to10 mHz with a 10 mV potential amplitude. According to the ISO 10993–15:2000 standard, immersion test was performed in 0.9 wt% NaCl solution at 37 °C for 7 days with 0.8 mL/ cm2 immersion ratio. Ions releasing concentration of samples was measured by atomic absorption spectroscopy (AAS) Z000. Passive film was analyzed by XPS using the Al Ka X-ray source. 3. Results and discussion Fig. 1a and b show the effects of temperature and time of water treatment on polarization curves and self-corrosion current density (Icorr). Icorr was obtained by fitting the Tafel regions. With increase of temperature and time, Icorr obviously decrease. In addition, no obvious changes were observed on pitting potential after treatment. Fig. 1c and d show the ions releasing concentration of HNNFS after water treatment, and Fig. 1e presents the comparison of ions releasing concentration of HNNFS and 316L stainless steel before and after treatment with nitric acid. As Fe and Mn are main
197
releasing ions, ions releasing concentration of HNNFS only includes these two ions. For 316L, Ni ions are also included. Fig. 1e shows that the general corrosion resistance of HNNFS is much weaker than that of 316L. In Fig. 1c and d, a sharp reduction of ions releasing concentration is observed with increasing temperature and time of water treatment. It is worth noting that, when treatment time is 600 min, the ions releasing concentration could decrease to 1/20 of untreated samples. That means the corrosion rate of water treated HNNFS could dramatically reduce to 1/20 of the untreated. Besides, Fig. 1e indicates that the general corrosion resistance of water treated HNNFS could be much better than that of 316L and HNNFS passivated by common nitric acid treatment. Therefore, this simple water treatment could significantly improve the general corrosion resistance of HNNFS. Similarly, water treatment has been successfully used to enhance the pitting corrosion resistance of 316L stainless steel [10]. To explore the quality and thickness of passive film, EIS analysis was conducted, and EIS results are showed in Fig. 2. The equivalent electrical circuit is also shown in Fig. 2, which refers to previous paper [11]. It includes solution resistance Rs, passive film resistance R1, passive film capacitance C, charge transfer resistance R2 and double-layer capacitance Q. Due to that the passive film is related to R1 and C1, only fitting data of R1 and C1 are listed in Table 1. As temperature and time increase, R1 gradually increases, which indicates that passive film quality becomes higher [11]. In addition, previous research shows that passive film thickness is inversely proportional to passive film capacitance [12]. Thus, the decrease of C1 indicates that passive film thickens as temperature and time increase. Those results further support the results from polarization curves and immersion test.
Fig. 1. Effects of temperature and time of water treatment on polarization curves, self-corrosion current (a and b) and ions releasing concentration (c and d); HNNFS and 316LSS before and after treatment by nitric acid (e); the error bars are total error.
198
Y. Yang et al. / Materials Letters 251 (2019) 196–200
Fig. 2. Effects of temperature (a and c) and time (b and d) of treatment on electrochemical impedance spectra; equivalent circuit for EIS.
Table 1 Passive film resistance and capacitance based on the equivalent circuit. R1 (105 X cm 25 °C 50 °C 75 °C 95 °C 10 min 60 min 300 min 600 min
3.41 ± 1.01 8.59 ± 2.57 13.50 ± 0.62 14.00 ± 3.66 8.47 ± 2.80 14.00 ± 3.66 14.10 ± 2.52 25.20 ± 5.47
2
)
C1 (10
5
F cm
2
)
6.33 ± 1.40 4.01 ± 0.38 3.57 ± 0.24 3.20 ± 3.81 4.96 ± 1.42 3.20 ± 0.38 3.11 ± 0.42 2.90 ± 0.31
In order to explore thickness and composition of passive film, XPS analysis is conducted. Fig. 3a shows the depth distribution of oxygen on temperature and time. Passive film thickness was determined by the oxygen content decreases to half of that at the surface. Hence, passive film thickness is 2–3 nm, and it thickens with increase of temperature and time. The variation trend of passive film thickness is consistent with EIS results. Fig. 3b presents that the Cr/Fe ratio in passive film increase with temperature and time. Those results indicate that temperature and time of water treatment facilitate Cr enrichment in passive film. According to the potential-pH diagram [13], during water treatment, the Cr oxide could stably exist in passive film, while Fe and Mn would dis-
solute as Fe and Mn ions. Hence, the Cr enrichment in passive film should be caused by the selective dissolution of Fe and Mn during water treatment [14]. Besides, compared with traditional stainless steel, weak general corrosion resistance of HNNFS could decrease the difficulty of Cr enrichment by water treatment. As shown in Fig. 3, the Cr 2p3/2 spectrums of all samples consist of three peaks including metallic Cr, Cr2O3 and Cr(OH)3. And the passive film formed at 95 °C contains more Cr2O3 and less metallic Cr than that formed at 25 °C. According to point defect model, the oxide film of stainless steels grows and thickens by diffusion of metal ions and oxygen [14]. At the passivation state, the diffusion process of oxygen becomes a controlling factor [15]. For HNNFS, oxygen atoms diffuse inward and react with Cr atoms to form Cr2O3. In this case, high temperature could promote the oxygen diffusion and form more Cr2O3 [16]. This should be the reason for temperature increase to enhance the general corrosion of HNNFS. Similarly, both Cr and oxygen contents are greatly increased in passive film as the extension of time, as shown in Fig. 3a and b. But Cr2O3 just slightly increases, while metallic Cr significantly increases. This is different with acid treatment. Study shows that, with treatment time increase, Cr2O3 greatly increased in passive film of stainless steel after HNO3 treatment [17]. For water treatment, dissolved oxygen in water is the oxidant. Although dissolved oxygen does not have strong oxidation ability as nitric acid, water
Y. Yang et al. / Materials Letters 251 (2019) 196–200
199
Fig. 3. Depth distribution of O (a) and Cr/Fe ration (b) at different temperature and time, XPS spectrum of Cr in passive film after treatment for 25 °C (c), 95 °C (d), 10 min (e) and 600 min (f).
treatment could concentrate more metallic Cr in passive film. By self-passivation, these Cr could react with dissolved oxygen and form more Cr2O3. Thus, the passive film on HNNFS could become more protective. Hence, water treatment could successfully enhance the general corrosion resistance of HNNFS.
to 1/20 of the untreated HNNFS and 1/3 of 316L stainless steel after common HNO3 treatment. Cr enrichment and thickness increase of passive film contributed to the improvement of general corrosion resistance of HNNFS. Declaration of Competing Interest
4. Conclusions In summary, a simple water treatment was successfully developed to enhance the general corrosion resistance of HNNFS. After treatment, the corrosion rate of HNNFS could dramatically reduce
We confirm that all the authors have checked the manuscript and have agreed to the submission and there is no financial interest to report. We certify that the submission is original work and is not under review at any other publication. If this manuscript can be
200
Y. Yang et al. / Materials Letters 251 (2019) 196–200
accepted, it will not be published elsewhere in the same form, in English or in any other language, without the written consent of the copyright-holder. Acknowledgment This work was supported by the National Natural Science Foundation of China [grant number 51801220]. References [1] [2] [3] [4]
Q.Z. Chen, G.A. Thouas, Mater. Sci. Eng. R 87 (2015) 1–57. M. Talha, C.K. Behera, O.P. Sinha, Mater. Sci. Eng. C 33 (2013) 3563–3575. Q.C. Wang, B.C. Zhang, Y.B. Ren, Corros. Sci. 145 (2018) 55–66. Q.C. Wang, B.C. Zhang, Y.B. Ren, Corros. Sci. 123 (2017) 351–355.
[5] R.F.V.V. Jaimes, M.L.C.D.A. Afonso, S.O. Rogero, Mater. Lett. 64 (2010) 1476– 1479. [6] Y.B. Ren, K. Yang, B.C. Zhang, Mater. Lett. 59 (2005) 1785–1789. [7] R. Köster, M. Sommerauer, J. Kähler, Lancet 356 (2000) 1895–1897. [8] M. Kemp, A.V. Bennekom, F.P.A. Robinson, Mater. Sci. Eng. A 199 (1995) 183– 194. [9] J.S. Noh, N.J. Laycock, W. Gao, D.B. Wells, Corros. Sci. 42 (2000) 2069–2084. [10] P.E. Klages, Z. Bai, M. Lobban, Electrochem. Commun. 15 (2012) 54–58. [11] G. Rondelli, P. Torricelli, M. Fini, Biomaterials 26 (2005) 739–744. [12] D. Wallindser, J. Pan, C. Leygrafa, Corros. Sci. 41 (1999) 275–289. [13] M. Pourbaix, Lectures on Electrochemical Corrosion, 1st ed., Plenum Press, New York. [14] C.-O.A. Olsson, D. Landolt, Electrochim. Acta 48 (2003) 1093–1104. [15] D.D. Macdonald, Electrochim. Acta 56 (2011) 1761–1772. [16] A.J. Bard, L.R. Faulkner, Electrochemical Methods Fundamentals and Application, 2nd ed., Wiley, New York. [17] J. Liu, T. Zhang, G.Z. Meng, Corros. Sci. 91 (2015) 232–244.