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Influence of grain boundary character distribution and random high angle grain boundaries networks on intergranular corrosion in high purity copper
Materials Letters 253 (2019) 424–426
Contents lists available at ScienceDirect
Materials Letters journal homepage: www.elsevier.com/locate/mlblue
Influence of grain boundary character distribution and random high angle grain boundaries networks on intergranular corrosion in high purity copper Yuan Yuan a,⇑, Youdong Jiang a, Jiang Zhou b, Guoyong Liu b, Xiao Ren c a b c
School of Materials Science and Engineering, Chongqing University, Chongqing 400044, China The State Key Laboratory of Transmission & Distribution Equipments and Power System Safety and New Technology, Chongqing University, Chongqing 400044, China Electric Power Research Institute, State Grid Chongqing Electric Power Company, Chongqing 401123, China
a r t i c l e
i n f o
Article history: Received 18 July 2019 Received in revised form 26 July 2019 Accepted 29 July 2019 Available online 30 July 2019 Keywords: Corrosion Grain boundaries High purity copper Grain boundary junctions Microstructure Multiple-twinning
a b s t r a c t Recently, as vital factors for corrosion resistance, grain boundary character distribution and random high angle grain boundaries networks gradually gained extensive attention. And grain boundary engineering was widely used in improving intergranular corrosion resistance of face-centered-cubic materials, such as austenitic stainless steel, nickel-based alloy and lead alloy, etc. But the relevant research on highpure copper was rarely studied. In this work, the intergranular corrosion behavior of high purity copper was investigated by potentiodynamic polarization tests in 0.1 M sodium chloride. And the influence of grain boundary character distribution (GBCD) and random high angle grain boundaries network (RHGBN) connectivity were explored. The contribution of multiple-twinning process to interrupt RHGBN connectivity was analyzed. Results clearly demonstrated that GBE samples all exhibited a high P resistance to intergranular corrosion (IGC), particularly, sample with higher fraction of low- CSL boundaries (GBE-1) or with lower RHGBN connectivity (GBE-3) both had a higher resistance to IGC. Multipletwinning process during annealing was the key factor to interrupt the connectivity of random high angle boundaries network. Ó 2019 Published by Elsevier B.V.
1. Introduction Grain boundary engineering (GBE) had long been a promising method to mitigate the intergranular corrosion (IGC), usually for the face-centered-cubic materials with low to medium stacking fault energy [1,2]. A mass of related researches about austenitic stainless steel, nickel-based alloy and aluminium alloy were investigated [3,4]. Via optimizing grain boundary character distribution (GBCD), 304L austenitic stainless steel exhibited remarkable resistance to IGC [5]. Several parameters to describe the optimized grain boundary network had been proposed. It was indicated that stress corrosion cracking behavior of alloy 600 was tremendously affected by types of grain boundaries, triple junctions and random high angle grain boundaries networks (RHGBN) [6]. The existence of long twin boundary chains would decrease susceptibility to intergranular attack of 316 stainless steel [7]. However, as a highly sensitive mental to IGC, there were less researches on the high purity copper. ⇑ Corresponding author. E-mail address: [email protected] (Y. Yuan). https://doi.org/10.1016/j.matlet.2019.07.125 0167-577X/Ó 2019 Published by Elsevier B.V.
GBCD and connectivity of RHGBN remained key parameters [8,9], which would prevent the initiation and propagation of IGC crack. In this work, the influence of grain boundary character distribution (GBCD) and random high angle grain boundaries network (RHGBN) connectivity of intergranular corrosion behavior were investigated for high purity copper samples after different thermal-mechanical processing (TMP). 2. Experimental section The material used in this work was as-extruded copper winding, obtained from transformer factory. This material was a high purity copper, with no traces of sulfur and minimal amount of oxygen. Subsequently, copper windings were cold rolled 5% and 10% (reduction of thickness), respectively. Part of 5% deformation samples were subjected to a heat treatment of 5 min at 200 °C and followed by an immediate water quench (WQ), producing the conventional sample (non-GBE) of this work. To obtain GBE samples, the rest of 5% and 10% deformation samples were annealed at 650 °C for 10 min and WQ, designated GBE-1 and GBE-3. Ultimately, the TMP for GBE-1 was repeated two times to acquire GBE-2.
Y. Yuan et al. / Materials Letters 253 (2019) 424–426
All the samples were ground and electro-polished. Analysis of grain boundary structure was made by using HKLChannel-5 EBSD detector, interfaced to a Zeiss Auriga FIB-SEM. The Palumbo–Aust P 5/6 criterion (Dhmax = 15° ) was used to define the CSL boundaries. The IGC behavior of samples was measured using the potentiodynamic polarization tests in 0.1 M sodium chloride. The electrochemical cell was a typical three electrode arrangement with a saturated calomel electrode (SCE) as reference electrode, a Pt-grid as counter electrode and the sample as working electrode. Samples with an exposed area of 1 cm2 were ground and electropolished. The open circuit potential (OCP)-time was measured until stabilized. Polarization curves were recorded from 300 mV to 100 mV, the scan rate was 2 mVs 1.
3. Results and discussion The intergranular corrosion behavior of high purity copper had been studied by potentiodynamic polarization Curves. Fig. 1 (a) showed the representative potentiodynamic polarization behavior of samples. By using Tafel extrapolation approach [10], corrosion current density (icorr) and corrosion potential (Ecorr) from the polarization curves were gained in Fig. 1 (b). It could be seen that little difference in Ecorr was observed between non-GBE, GBE-1 and GBE-2, whereas that of GBE-3 had a more noble value. Meanwhile, the icorr values of Non-GBE, GBE-1, GBE-2 and GBE-3 were 5.14 10 5, 2.77 10 5, 3.65 10 5 and 1.94 10 5 A/cm2 respectively. It was suggest that the corrosion resistance of GBE-
425
samples with different TMP methods was improved, especially GBE-1 and GBE-3. P 5/6 Based on the Palumbo–Aust criterion (Dhmax = 15° ), proP portions of low- CSL boundaries were presented in Fig. 2(a).Via P different TMP methods, the fractions of low- CSL boundaries of GBE samples increased drastically. It could be seen the total fracP P P P tion of 3, 9, 27a and 27b for non-GBE is 36.9%. After proP cessing, all the fractions of low- CSL boundaries were higher than 71.0%, especially for GBE-1, which reached 81.5%. Fig. 2(b) depicted conditions of grain cluster formation, grain cluster- also known as twin-related domain- was involving iterated twinning operations starting from a single nucleus [11]. The large size of grain clusters was a prominent feature of GBE-processed microstructures and the key parameter to judge RHGBN. The large size grain cluster could P not only increase the fraction of low- CSL boundaries, but also interrupt the connectivity of RHGBN. For non-GBE samples, there were no significant differences between average size of grain and grain cluster, which indicated the high connectivity of RHGBN. Meanwhile, a notable increase in average sizes of grain cluster had been realized following GBE-type TMP, especially GBE-1 (77.4 lm) and GBE-3 (170.2 lm). The max size of grain cluster was also compared, which exhibiting the same tendency with average size. OIM maps and corresponding RHGBN connectivity maps were employed to analyze RHGBN connectivity of different samples. Fig. 3(a) exhibited GBCD of non-GBE, with low prior strain (5%) coupled with incomplete annealing (200 °C, 5 min), grains still remained deformed. The annealing temperature was so low that growth of grains and migration of grain boundaries could not
Fig. 1. (a) Potentiodynamic polarization curves for non-GBE, GBE-1, GBE-2, GBE-3; (b) The corrosion potential (Ecorr) as a function of current density values (icorr).
Fig. 2. (a) Grain boundary character distributions (GBCDs) and (b) grain/grain cluster sizes of non-GBE, GBE-1, GBE-2 and GBE-3.
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were all disrupted by R3n boundaries, exhibiting pretty low RHGBN connectivity (as circled in Fig. 3 (h)). The number of cycles of a multiple-twinning process was approximately equal to the number of twins within the formed grain cluster [15]. From Fig. 2(b), number of grains per cluster were consistent with above analysis. The fraction of low-CSL grain boundaries and the connectivity of RHGBN were closely related to IGC resistance. From Figs. 2 and 3, there was no distinct difference in the total fraction of low-RCSL boundaries between GBE-2 and GBE-3, but GBE-3 exhibited a pretty low connectivity of RHGBN. Meanwhile, the corrosion current density (Fig. 1) reduced from 3.65 10 5 A/cm2 to 1.94 10 5 A/cm2, the corrosion potential increased from 0.166 V to 0.041 V. Owing to the interruption of RHGBN, the IGC resistance was greatly enhanced. As for GBE-1, the total fraction of low-RCSL boundaries reached to 81.5% and still remained moderate RHGBN connectivity. With such so high fraction of low-RCSL boundaries, this sample exhibited a good anti-IGC property and was only slightly blew GBE-3. 4. Conclusions The intergranular corrosion behavior in 0.1 M sodium chloride of high purity copper demonstrated that both of the samples with high fraction of low-RCSL boundaries or low connectivity of RHGBN could exhibit a good anti-IGC property. Large size of grain clusters was the dominating parameter to judge RHGBN. It was indicated that sample with larger mean size of grain cluster always appeared a lower RHGBN connectivity. Multiple-twinning process during annealing was the key factor to interrupt the connectivity of RHGBN, for the cycles of multiple-twinning would cause larger clusters and then interrupt the connectivity of RHGBN. Fig. 3. OIM maps and corresponding RHGBN connectivity maps of (a, b) non-GBE, (c, d) GBE-1, (e, f) GBE-2 and (g, h) GBE-3.
occur. It depicted that the majority of the twin-chain were parallel and short, terminating within a grain. Consequently, the RHGBN of non-GBE remained intact and extremely high connectivity of RHGBN was observed (refer Fig. 3(b)). In the case of GBE-1, the low prior strain plus high temperature promoted abnormal grain growth (also called ‘growth accident’ or ‘popping out’), twinning operations could occur to the single grain nucleus [12,13]. Due to the low density of nucleation site, only a small number of new grain nucleuses formed, which leading to the nucleus generally had more space to grow [11]. During this period, twinning operations could occur again and again with a single grain nucleus, which named multiple-twinning [14]. These new grain nucleuses grew until all the prior strained were consumed. Thus, at the end of recrystallization, the single grain nucleus grew up to a huge grain cluster. Fig. 3(c) and (d) showed some part of R3n boundaries appeared to be an integral part of the RHGBN. It could be seen almost all inner random boundaries were interrupted (the typical interruptions of grain boundaries(inner cluster) were circled in blue), but for the inadequate multiple-twinning operation of single TMP, only a few of R3n boundaries could migrate to the boundary of cluster (the typical interruptions of cluster boundaries(margin) were circled in red). Therefore, GBE-1 exhibited moderate RHGBN connectivity. As was shown in Fig. 3(e) and (f), the connectivity of RHGBN for GBE-2 was hardly interrupted. For the sample with 10% deformation, the density of nucleation sites during annealing were so high that grains would encounter quickly and had no space to grow. Therefore, multiple-twinning process was insufficient. As for GBE-3, the multiple 5% deformation plus short-time annealing at high-temperature increased the cycle-index of multipletwinning. From Fig. 3 (g) and (h), the RHGBN of grains and clusters
Declaration of Competing Interest We declare that we do not have any commercial or associative interest that represents a conflict of interest in connection with the work submitted. Acknowledgement The authors wish to acknowledge the financial supports of the National Natural Science Foundation of China (project No. 51677015 and 51437001). References [1] L. Yang, S. Gao, B. Deng, Z. Cheng, Ind. Eng. Chem. Res. 56 (32) (2017) 9124– 9134. [2] Y. Yuan, X. He, Z. Xu, X. Guo, H. Xia, Int. J. Electrochem. Sci. 10 (12) (2015) 10806–10820. [3] A.B. Straumal, V.A. Yardley, B.B. Straumal, A.O. Rodin, JMatS 50 (13) (2015) 4762–4771. [4] B.B. Straumal, A.A. Mazilkin, S.G. Protasova, G. Schuetz, A.B. Straumal, B. Baretzky, J. Mater. Eng. Perform. 25 (8) (2016) 3303–3309. [5] S.K. Pradhan, P. Bhuyan, S. Mandal, Corros. Sci. 139 (2018) 319–332. [6] A. Telang, A.S. Gill, M. Kumar, S. Teysseyre, D. Qian, S.R. Mannava, V.K. Vasudevan, Acta Mater. 113 (2016) 180–193. [7] T. Liu, S. Xia, D. Du, Q. Bai, L. Zhang, Y. Lu, Mater. Lett. 234 (2019) 201–204. [8] W. Kuang, G.S. Was, C. Miller, M. Kaufman, T. Alam, B. Gwalani, R. Banerjee, Corros. Sci. 130 (2018) 126–137. [9] Y. Zhang, X. Feng, C. Song, H. Wang, B. Yang, Z. Wang, Mrs Communications 9 (1) (2019) 251–257. [10] M. Behpour, S.M. Ghoreishi, M. Khayatkashani, N. Soltani, Mater. Chem. Phys. 131 (3) (2012) 621–633. [11] C.M. Barr, A.C. Leff, R.W. Demott, R.D. Doherty, M.L. Taheri, Acta Mater. 144 (2018) 281–291. [12] H. Jiang, J. Dong, M. Zhang, Z. Yao, J. Alloys Compd. 735 (2018) 1520–1535. [13] P. Diko, Superconductor Sci. Technol. 13 (8) (2000) 1202–1213. [14] V.Y. Gertsman, C.H. Henager, Interface Sci. 11 (4) (2003) 403–415. [15] T. Liu, S. Xia, Q. Bai, B. Zhou, Y. Lu, T. Shoji, Materials 12 (2) (2019) 242–259.
Contents lists available at ScienceDirect
Materials Letters journal homepage: www.elsevier.com/locate/mlblue
Influence of grain boundary character distribution and random high angle grain boundaries networks on intergranular corrosion in high purity copper Yuan Yuan a,⇑, Youdong Jiang a, Jiang Zhou b, Guoyong Liu b, Xiao Ren c a b c
School of Materials Science and Engineering, Chongqing University, Chongqing 400044, China The State Key Laboratory of Transmission & Distribution Equipments and Power System Safety and New Technology, Chongqing University, Chongqing 400044, China Electric Power Research Institute, State Grid Chongqing Electric Power Company, Chongqing 401123, China
a r t i c l e
i n f o
Article history: Received 18 July 2019 Received in revised form 26 July 2019 Accepted 29 July 2019 Available online 30 July 2019 Keywords: Corrosion Grain boundaries High purity copper Grain boundary junctions Microstructure Multiple-twinning
a b s t r a c t Recently, as vital factors for corrosion resistance, grain boundary character distribution and random high angle grain boundaries networks gradually gained extensive attention. And grain boundary engineering was widely used in improving intergranular corrosion resistance of face-centered-cubic materials, such as austenitic stainless steel, nickel-based alloy and lead alloy, etc. But the relevant research on highpure copper was rarely studied. In this work, the intergranular corrosion behavior of high purity copper was investigated by potentiodynamic polarization tests in 0.1 M sodium chloride. And the influence of grain boundary character distribution (GBCD) and random high angle grain boundaries network (RHGBN) connectivity were explored. The contribution of multiple-twinning process to interrupt RHGBN connectivity was analyzed. Results clearly demonstrated that GBE samples all exhibited a high P resistance to intergranular corrosion (IGC), particularly, sample with higher fraction of low- CSL boundaries (GBE-1) or with lower RHGBN connectivity (GBE-3) both had a higher resistance to IGC. Multipletwinning process during annealing was the key factor to interrupt the connectivity of random high angle boundaries network. Ó 2019 Published by Elsevier B.V.
1. Introduction Grain boundary engineering (GBE) had long been a promising method to mitigate the intergranular corrosion (IGC), usually for the face-centered-cubic materials with low to medium stacking fault energy [1,2]. A mass of related researches about austenitic stainless steel, nickel-based alloy and aluminium alloy were investigated [3,4]. Via optimizing grain boundary character distribution (GBCD), 304L austenitic stainless steel exhibited remarkable resistance to IGC [5]. Several parameters to describe the optimized grain boundary network had been proposed. It was indicated that stress corrosion cracking behavior of alloy 600 was tremendously affected by types of grain boundaries, triple junctions and random high angle grain boundaries networks (RHGBN) [6]. The existence of long twin boundary chains would decrease susceptibility to intergranular attack of 316 stainless steel [7]. However, as a highly sensitive mental to IGC, there were less researches on the high purity copper. ⇑ Corresponding author. E-mail address: [email protected] (Y. Yuan). https://doi.org/10.1016/j.matlet.2019.07.125 0167-577X/Ó 2019 Published by Elsevier B.V.
GBCD and connectivity of RHGBN remained key parameters [8,9], which would prevent the initiation and propagation of IGC crack. In this work, the influence of grain boundary character distribution (GBCD) and random high angle grain boundaries network (RHGBN) connectivity of intergranular corrosion behavior were investigated for high purity copper samples after different thermal-mechanical processing (TMP). 2. Experimental section The material used in this work was as-extruded copper winding, obtained from transformer factory. This material was a high purity copper, with no traces of sulfur and minimal amount of oxygen. Subsequently, copper windings were cold rolled 5% and 10% (reduction of thickness), respectively. Part of 5% deformation samples were subjected to a heat treatment of 5 min at 200 °C and followed by an immediate water quench (WQ), producing the conventional sample (non-GBE) of this work. To obtain GBE samples, the rest of 5% and 10% deformation samples were annealed at 650 °C for 10 min and WQ, designated GBE-1 and GBE-3. Ultimately, the TMP for GBE-1 was repeated two times to acquire GBE-2.
Y. Yuan et al. / Materials Letters 253 (2019) 424–426
All the samples were ground and electro-polished. Analysis of grain boundary structure was made by using HKLChannel-5 EBSD detector, interfaced to a Zeiss Auriga FIB-SEM. The Palumbo–Aust P 5/6 criterion (Dhmax = 15° ) was used to define the CSL boundaries. The IGC behavior of samples was measured using the potentiodynamic polarization tests in 0.1 M sodium chloride. The electrochemical cell was a typical three electrode arrangement with a saturated calomel electrode (SCE) as reference electrode, a Pt-grid as counter electrode and the sample as working electrode. Samples with an exposed area of 1 cm2 were ground and electropolished. The open circuit potential (OCP)-time was measured until stabilized. Polarization curves were recorded from 300 mV to 100 mV, the scan rate was 2 mVs 1.
3. Results and discussion The intergranular corrosion behavior of high purity copper had been studied by potentiodynamic polarization Curves. Fig. 1 (a) showed the representative potentiodynamic polarization behavior of samples. By using Tafel extrapolation approach [10], corrosion current density (icorr) and corrosion potential (Ecorr) from the polarization curves were gained in Fig. 1 (b). It could be seen that little difference in Ecorr was observed between non-GBE, GBE-1 and GBE-2, whereas that of GBE-3 had a more noble value. Meanwhile, the icorr values of Non-GBE, GBE-1, GBE-2 and GBE-3 were 5.14 10 5, 2.77 10 5, 3.65 10 5 and 1.94 10 5 A/cm2 respectively. It was suggest that the corrosion resistance of GBE-
425
samples with different TMP methods was improved, especially GBE-1 and GBE-3. P 5/6 Based on the Palumbo–Aust criterion (Dhmax = 15° ), proP portions of low- CSL boundaries were presented in Fig. 2(a).Via P different TMP methods, the fractions of low- CSL boundaries of GBE samples increased drastically. It could be seen the total fracP P P P tion of 3, 9, 27a and 27b for non-GBE is 36.9%. After proP cessing, all the fractions of low- CSL boundaries were higher than 71.0%, especially for GBE-1, which reached 81.5%. Fig. 2(b) depicted conditions of grain cluster formation, grain cluster- also known as twin-related domain- was involving iterated twinning operations starting from a single nucleus [11]. The large size of grain clusters was a prominent feature of GBE-processed microstructures and the key parameter to judge RHGBN. The large size grain cluster could P not only increase the fraction of low- CSL boundaries, but also interrupt the connectivity of RHGBN. For non-GBE samples, there were no significant differences between average size of grain and grain cluster, which indicated the high connectivity of RHGBN. Meanwhile, a notable increase in average sizes of grain cluster had been realized following GBE-type TMP, especially GBE-1 (77.4 lm) and GBE-3 (170.2 lm). The max size of grain cluster was also compared, which exhibiting the same tendency with average size. OIM maps and corresponding RHGBN connectivity maps were employed to analyze RHGBN connectivity of different samples. Fig. 3(a) exhibited GBCD of non-GBE, with low prior strain (5%) coupled with incomplete annealing (200 °C, 5 min), grains still remained deformed. The annealing temperature was so low that growth of grains and migration of grain boundaries could not
Fig. 1. (a) Potentiodynamic polarization curves for non-GBE, GBE-1, GBE-2, GBE-3; (b) The corrosion potential (Ecorr) as a function of current density values (icorr).
Fig. 2. (a) Grain boundary character distributions (GBCDs) and (b) grain/grain cluster sizes of non-GBE, GBE-1, GBE-2 and GBE-3.
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Y. Yuan et al. / Materials Letters 253 (2019) 424–426
were all disrupted by R3n boundaries, exhibiting pretty low RHGBN connectivity (as circled in Fig. 3 (h)). The number of cycles of a multiple-twinning process was approximately equal to the number of twins within the formed grain cluster [15]. From Fig. 2(b), number of grains per cluster were consistent with above analysis. The fraction of low-CSL grain boundaries and the connectivity of RHGBN were closely related to IGC resistance. From Figs. 2 and 3, there was no distinct difference in the total fraction of low-RCSL boundaries between GBE-2 and GBE-3, but GBE-3 exhibited a pretty low connectivity of RHGBN. Meanwhile, the corrosion current density (Fig. 1) reduced from 3.65 10 5 A/cm2 to 1.94 10 5 A/cm2, the corrosion potential increased from 0.166 V to 0.041 V. Owing to the interruption of RHGBN, the IGC resistance was greatly enhanced. As for GBE-1, the total fraction of low-RCSL boundaries reached to 81.5% and still remained moderate RHGBN connectivity. With such so high fraction of low-RCSL boundaries, this sample exhibited a good anti-IGC property and was only slightly blew GBE-3. 4. Conclusions The intergranular corrosion behavior in 0.1 M sodium chloride of high purity copper demonstrated that both of the samples with high fraction of low-RCSL boundaries or low connectivity of RHGBN could exhibit a good anti-IGC property. Large size of grain clusters was the dominating parameter to judge RHGBN. It was indicated that sample with larger mean size of grain cluster always appeared a lower RHGBN connectivity. Multiple-twinning process during annealing was the key factor to interrupt the connectivity of RHGBN, for the cycles of multiple-twinning would cause larger clusters and then interrupt the connectivity of RHGBN. Fig. 3. OIM maps and corresponding RHGBN connectivity maps of (a, b) non-GBE, (c, d) GBE-1, (e, f) GBE-2 and (g, h) GBE-3.
occur. It depicted that the majority of the twin-chain were parallel and short, terminating within a grain. Consequently, the RHGBN of non-GBE remained intact and extremely high connectivity of RHGBN was observed (refer Fig. 3(b)). In the case of GBE-1, the low prior strain plus high temperature promoted abnormal grain growth (also called ‘growth accident’ or ‘popping out’), twinning operations could occur to the single grain nucleus [12,13]. Due to the low density of nucleation site, only a small number of new grain nucleuses formed, which leading to the nucleus generally had more space to grow [11]. During this period, twinning operations could occur again and again with a single grain nucleus, which named multiple-twinning [14]. These new grain nucleuses grew until all the prior strained were consumed. Thus, at the end of recrystallization, the single grain nucleus grew up to a huge grain cluster. Fig. 3(c) and (d) showed some part of R3n boundaries appeared to be an integral part of the RHGBN. It could be seen almost all inner random boundaries were interrupted (the typical interruptions of grain boundaries(inner cluster) were circled in blue), but for the inadequate multiple-twinning operation of single TMP, only a few of R3n boundaries could migrate to the boundary of cluster (the typical interruptions of cluster boundaries(margin) were circled in red). Therefore, GBE-1 exhibited moderate RHGBN connectivity. As was shown in Fig. 3(e) and (f), the connectivity of RHGBN for GBE-2 was hardly interrupted. For the sample with 10% deformation, the density of nucleation sites during annealing were so high that grains would encounter quickly and had no space to grow. Therefore, multiple-twinning process was insufficient. As for GBE-3, the multiple 5% deformation plus short-time annealing at high-temperature increased the cycle-index of multipletwinning. From Fig. 3 (g) and (h), the RHGBN of grains and clusters
Declaration of Competing Interest We declare that we do not have any commercial or associative interest that represents a conflict of interest in connection with the work submitted. Acknowledgement The authors wish to acknowledge the financial supports of the National Natural Science Foundation of China (project No. 51677015 and 51437001). References [1] L. Yang, S. Gao, B. Deng, Z. Cheng, Ind. Eng. Chem. Res. 56 (32) (2017) 9124– 9134. [2] Y. Yuan, X. He, Z. Xu, X. Guo, H. Xia, Int. J. Electrochem. Sci. 10 (12) (2015) 10806–10820. [3] A.B. Straumal, V.A. Yardley, B.B. Straumal, A.O. Rodin, JMatS 50 (13) (2015) 4762–4771. [4] B.B. Straumal, A.A. Mazilkin, S.G. Protasova, G. Schuetz, A.B. Straumal, B. Baretzky, J. Mater. Eng. Perform. 25 (8) (2016) 3303–3309. [5] S.K. Pradhan, P. Bhuyan, S. Mandal, Corros. Sci. 139 (2018) 319–332. [6] A. Telang, A.S. Gill, M. Kumar, S. Teysseyre, D. Qian, S.R. Mannava, V.K. Vasudevan, Acta Mater. 113 (2016) 180–193. [7] T. Liu, S. Xia, D. Du, Q. Bai, L. Zhang, Y. Lu, Mater. Lett. 234 (2019) 201–204. [8] W. Kuang, G.S. Was, C. Miller, M. Kaufman, T. Alam, B. Gwalani, R. Banerjee, Corros. Sci. 130 (2018) 126–137. [9] Y. Zhang, X. Feng, C. Song, H. Wang, B. Yang, Z. Wang, Mrs Communications 9 (1) (2019) 251–257. [10] M. Behpour, S.M. Ghoreishi, M. Khayatkashani, N. Soltani, Mater. Chem. Phys. 131 (3) (2012) 621–633. [11] C.M. Barr, A.C. Leff, R.W. Demott, R.D. Doherty, M.L. Taheri, Acta Mater. 144 (2018) 281–291. [12] H. Jiang, J. Dong, M. Zhang, Z. Yao, J. Alloys Compd. 735 (2018) 1520–1535. [13] P. Diko, Superconductor Sci. Technol. 13 (8) (2000) 1202–1213. [14] V.Y. Gertsman, C.H. Henager, Interface Sci. 11 (4) (2003) 403–415. [15] T. Liu, S. Xia, Q. Bai, B. Zhou, Y. Lu, T. Shoji, Materials 12 (2) (2019) 242–259.