Ag by thermal treatment

Journal Pre-proof The improved corrosion and tribocorrosion properties of TiSiN/ Ag by thermal treatment

Yebiao Zhu, Minpeng Dong, Jinlong Li, Liping Wang PII:

S0257-8972(20)30106-7

DOI:

https://doi.org/10.1016/j.surfcoat.2020.125437

Reference:

SCT 125437

To appear in:

Surface & Coatings Technology

Received date:

22 October 2019

Revised date:

28 January 2020

Accepted date:

2 February 2020

Please cite this article as: Y. Zhu, M. Dong, J. Li, et al., The improved corrosion and tribocorrosion properties of TiSiN/Ag by thermal treatment, Surface & Coatings Technology (2020), https://doi.org/10.1016/j.surfcoat.2020.125437

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© 2020 Published by Elsevier.

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The improved corrosion and tribocorrosion properties of TiSiN/Ag by thermal treatment Yebiao Zhua,b, Minpeng Donga, Jinlong Lia,b,*, Liping Wanga,* a

Key Laboratory of Marine Materials and Related Technologies, Zhejiang Key

Laboratory of Marine Materials and Protective Technologies, Ningbo Institute of

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Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, PR China

Center of Materials Science and Optoelectronics Engineering, University of Chinese

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Academy of Sciences, Beijing 100049, PR China

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*Corresponding author: [email protected], [email protected]

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Abstract

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Keywords: anneal; tribocorrosion; porosity; residual stress

TiSiN and TiSiN/Ag coatings were prepared by multi ion arc plating and annealed

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at 650 ℃ for 5 h. It was found that the annealed coatings had the better corrosion and tribocorrosion properties than as-deposited coatings. The annealed TiSiN coatings exhibited a slower failure process in electrochemical impedance spectroscopy in test due to the reduction of porosities. Moreover, the annealing process can decrease the residual stresses in the coating which can lead to the low coefficient of friction during tribocorrosion tests. What’s more, Ag played an important role in tribocorrosion experiment in TiSiN/Ag multilayer coatings. In general, the thermal treatment can improve the corrosion and tribocorrosion properties of the coatings and annealed TiSiN/Ag coatings exhibited the best tribocorrosion performance.

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1 Introduction For now, Marine resource has become a strategic area for each country and the marine materials are therefore facing a big challenge due to the extreme environment, such as high humidity and high salinity[1]. Traditional materials would be corroded in a very short time and thus a material with anti-corrosion property is required.

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Titanium alloys are employed in marine engineering on account of their strengths like anti-corrosion property, low-density, high strength-to-weight ratio and so forth [2].

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Nevertheless, the titanium alloys do not have a good performance in friction process.

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Namely, titanium is a bad choice for corrosive environments only when associated to

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wear [3]. Hence, the PVD coatings are needed to protect the alloys. In marine and

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mechanical environment, the friction always accompanied by corrosion process

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(so-called tribocorrosion) and thus applied coatings have to perform good tribocorrosion behaviors. According to the previous researches, the nitride PVD

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coatings had a high performance with respect to corrosion [4] as well as tribocorrosion protection[5-7]. However, some usual coatings, like TiN, CrN, have some distinct disadvantages such as poor oxidation resistance [8, 9]and they can hardly reach the anti-corrosion requirement [10]. In this work, TiSiN was selected due to its high hardness, oxidation as well as the corrosion resistance thanks to Si doping [11, 12]. On the other hand, the pure TiSiN coatings still have a high coefficient of friction (COF) and thus Ag layers are inserted into the TiSiN layer due to the lubrication effect[13]. According to Dang[14], co-deposited TiSiN-Ag coating have poor mechanical properties due to the doping of soft metal. Therefore, the multilayer

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structure coatings are supposed to exhibit excellent tribocorrosion properties. It's worth noting that the as-deposited coatings are always not compact enough to protect the substrate perfectly especially in marine environment[15, 16]. On account of the existence of the intrinsic porosity in the coating [16, 17], corrosive ions can diffuse through the coating and contact with the substrate. It is expected that

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annealing process can decrease the porosity of the coating and make it compact. Meanwhile, annealing can also release the residual stress in the coating which can

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improve the tribology behavior of the coating [18, 19].

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In this work, TiSiN and TiSiN/Ag coatings are prepared by multi-arc ion plating

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(which has many superiorities: fast deposition rate, strong adhesion) for comparison

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and as-deposited coatings are annealed at 650 ℃ for 5 h (which is in the temperature

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range of engine working) to explore the effect of annealing process. The corrosion and tribocorrison tests were conducted to evaluate the coatings protective capability to

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substrates. It is expected that the Ag layer and annealing process can make coatings more reliable in marine environment and it provides a new thought to design the coating with compact structure in marine applications. 2 Experimental details 2.1 Coating synthesis TiSiN and TiSiN/Ag coatings were prepared with multi-arc plating on Ti-6Al-4V alloys which consists of Al: 5.5%-6.75%, V:3.5%-4.5% and Ti (60 mm × 30 mm × 3 mm, fabricated by Baoji Titanium Industry Company Limited) in an industrial deposition system (Hauzer Flexicoat 850). The device chamber was equipped in three

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groups of cathodes (each group has three targets), two of which are TiSi targets (90 wt % Ti, 10 wt % Si; purity 99.99 wt%) and the other group is Ag target (purity 99.99 wt%). Before the deposition, the substrates were ultrasonic cleaned in acetone and ethanol and then mounted on a holder in the chamber. The chamber had to be evacuated until the base pressure was lower than 4 × 10-3 Pa and be heated to 450 ℃.

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The deposition process can be divided into two parts as following: (i) the ions sputter cleaning (using a substrate bias of -900, -1100 and -1200 V successively) was applied

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to remove the contaminations for better adhesion in Ar atmosphere (0.15 Pa). (ii) The

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TiSiN layer was deposited in N2 atmosphere (2.5 Pa) with a target current of 65 A and

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a substrate bias of -30 V and the Ag layer was deposited in Ar atmosphere (2.5 Pa)

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with a target current of 35 A and a substrate bias of -30 V. As for TiSiN monolayer

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coatings, the deposition process of TiSiN layer lasted for 65 min and a cycle for 6 period was employed to prepare the multilayer coatings (10 min for TiSiN layer and

cm.

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1min for Ag layer as one period). The distance between the source and substrate is 10

In order to study the effect of annealing process to the coating, both of the TiSiN monolayer and TiSiN/Ag multilayer coatings were placed in the tube furnace (GSL-1700X, Hefei kejing materials technology co., LTD) at 650 ℃ for 5 h under the pressure of 8 × 10-5 Pa. 2.2 Characterization The thicknesses and morphologies of the coatings were detected by scanning electron microscopy (SEM, Thermo scientific Verios G4 UC). The roughness of the

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as-deposited coatings was measured by laser scanning confocal microscope (Zeiss, LSM700). Scratch test was applied to evaluate the adhesion between the coatings and the substrates and Lc3 was regarded as the resluts. The parameters were as follows: the max load was 50N (initial load: 1 N), the speeding of a scratch test was 3 mm/min, and the length of the scratch track was 5 mm. Acoustic signal sensitivity and

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acquisition rate was 9, 30Hz, respectively. The structure of the coatings were investigated by X-ray diffraction (XRD), X-ray

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photoelectron spectroscopy (XPS) and transmission electron microscope (TEM). The

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XRD patterns were recorded on X-ray diffraction (Bruker D8 X-ray facility) using Cu

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Kα radiation (λ = 0.154 nm), which was carried out at 40 kV and 40 mA with a

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grazing incidence angle 2°. The scanning angle ranged from 20° to 100° with a 0.02°

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step size. The chemical bindings of the both coatings was studied by a Kratos spectrometer (AXIS UTLTRADLD, UK). XPS spectra were recorded on a Kratos

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spectrometer using monochromatic Al Kα radiation as the X-ray source with a photon energy (hν = 1486.7 eV). To gain an accurate peak separation, each spectra were calibrated according to the C 1s peak of the adventitious carbon (CHx) whose binding energy is about 284.8 eV. All curve-fitting procedures were carried out using a non-linear least squares fitting method employing the Gaussian-Lorentzian function and considering the background as linear or Shirley type. The microstructure of the coatings was studied in details by TEM, high-resolution TEM (HRTEM) (Tecnai F20, USA). The samples were prepared by focused ion beam (FIB, Zeiss Auriga) for TEM. 2.3 Corrosion and tribocorrosion properties

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To evaluate the corrosion and tribocorrosion properties of the coatings, electrochemical signals were collected by Modulab analytical while the tribology tests were carried out on Rtec Instruments. Three-electrode electrochemical working station was applied to conduct the electrochemical corrosion tests and Ag-AgCl electrode was set as reference electrode, platinum plate as counter electrode and the

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samples as working electrode. The electrochemical impedance spectroscopy (EIS) measurements were carried out before the tribocorrosion tests in the frequency range

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from 105 to 10−2 Hz. The used voltage amplitude of EIS measurements is 10 mV. The

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potentiodynamic polarization curves were recorded over the potential range from −1.0

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V to +1.5 V at a scan rate of 1 mV/s. The samples were fixed in an insulated fixture

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and immersed in artificial seawater (the components of the artificial seawater were

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listed in Table S1)[20]. Before the tests, the samples should be immersed in the artificial seawater until the OCP becoming stable. In the tribocorrosion tests, SiC balls

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with 6 mm in diameter were used as counter-balls and a load of 5 N with the reciprocating sliding speed of 20 mm/s was applied in the tests. The wear test cycle lasted for 30 min and wear track length is 5 mm. The tribocorrosion tests were performed under OCP condition and the potentiodynamic polarization curves were measured in the same way as corrosion tests. After the test, the three-dimensional shapes of the wear tracks were obtained by laser scanning confocal microscopy (LSCM, VK-X200K) and according to that, the wear rates were computed by normalizing the wear volume with the total sliding distance and the applied load. The morphologies of the wear tracks were detected by SEM. The anti-corrosion properties

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of the samples were evaluated by electrochemical impedance spectroscopy (EIS) results and the recorded data were fitted through ZSimpWin software using the electrical equivalent circuits. The porosities of (annealed) coatings are calculated by the following equation[21, 22]: Porosity =

𝑅𝑝 (𝑠𝑢𝑏𝑠𝑡𝑟𝑎𝑡𝑒) 𝑅𝑝 (𝑐𝑜𝑎𝑡𝑖𝑛𝑔)

× 100%

(1)

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where Rp(substrate) stands for the polarization resistance of the substrate and Rp(coating) is the measured polarization resistance of the coating. The polarisation

𝐵 𝑖𝑐𝑜𝑟𝑟

𝑏 𝑏

𝑎 𝑐 with B = 2.303(𝑏 +𝑏 𝑎

𝑐)

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𝑅𝑝 =

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resistance is obtained from the potentiodynamic polarization curves using Eq. 2. (2)

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where ba and bc are the Tafel slopes (V) and icorr is the corrosion current density (A

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cm-2).

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In order to explore the effects of annealing and tribocorrosion, XRD (Bruker D8 DISCOVER) was used to measure the residual stress of the coating before and after

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annealing and Raman spectra (Renishaw inVia Reflex) were applied to investigate the compositions generated in the wear track. In Raman spectra, Ar+ laser was employed as the excitation source with the 514.5 nm lines and the spectra were acquired over the range of 280-2080 cm-1 at 2 cm-1 resolution. Moreover, XRD technique was applied to measure residual stress with the sin2ψ method[23]. The stress was obtained by following equation[24]: 𝐸

𝜋

𝜕(2𝜃)

σ = 2(1+𝑣) 𝑐𝑡𝑔𝜃0 180° 𝜕(𝑠𝑖𝑛2 𝜑)

(3)

where 𝜃0 is the selected angle, E and υ are Young's modulus and Poisson's ratio of coating. In this work, TiN (200)-crystal plane (2θ = 42.5°) was selected as a reference

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due to its strongest diffraction peak in XRD patterns. And a sliding gravity evaluation method and a normal stress model were applied in stress values calculation. 3 Results and discussions 3.1 Characterization The cross-section images with surface morphologies of the TiSiN and TiSiN/Ag

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coating before and after annealing process detected by SEM are presented in Fig. 1. Microdroplets can be found on the surface which have a great influence on the

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roughness of the coatings. The thicknesses of the both coatings are measured to be

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about 2.0 μm. Several ultra-thin Ag layers are inserted in the TiSiN coating and

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remain structure of the TiSiN layer unchanged (columnar crystal can be observed in

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both coatings). In addition, because of the existence of the droplets, there would be

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more likely to be corroded compared to compact coatings.[25-27] After annealing process, there are a number of Ag particles found beside the droplets which can be

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attributed to the Ag diffusion along the margin of droplets. The results of the coatings adhesion tested by scratch test are presented in Fig. S1 and the values of both TiSiN and TiSiN/Ag coatings are about 26 N.

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Fig. 1 The cross-section images with surface morphologies of (a) TiSiN/Ag (b) TiSiN (c) annealed TiSiN/Ag and (d)TiSiN coatings

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The XRD patterns of the as-deposited and annealed TiSiN(/Ag) coatings are exhibited in Fig. 2a. And it can be found that there is no visible difference between the as-deposited and annealed coatings which implied that the annealing process in the vacuum do not generate any new phases in the coating. TiN (PDF#06-0642) phase (𝐹𝑚3̅𝑚) and the Ag phase (PDF#65-2871) (𝐹𝑚3̅𝑚) are observed and no Si peak is detected in XRD patterns. TiN (200) is the strongest peak in the patterns which is the main crystal plane in the coating. Furthermore, the Ag (111) and (200) sub-strong peaks are found as a result from Ag layers insertion. The Ti 2p, Si 2p, N 1s and Ag 3d XPS core level spectra before and after annealing are presented in Fig. 2b. In Fig. 2b1

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(Ti 2p), three groups of peaks at 455.1 eV and 460.8 eV, 456.3 eV and 462.4 eV, 458.4 eV and 464.2 eV are corresponding to TiN, N-Ti-O and TiO2, respectively[13]. The appearance of the N-Ti-O and TiO2 peaks can give credit to the O2 absorbing and oxidizing on the surface. Fig. 2b2 shows that the Si 2p peak at 101.8 eV and this peak is associated with Si3N4 [14]. Combined with the XRD results, it can thus concluded

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that the Si element exists in the coating as amorphous phases. The peaks at 396.2 eV and 397 eV and 398.8 eV in Fig. 2b3 (N 1s) further verified the existence of N-Ti-O,

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TiN and Si3N4[13]. Ag 3d3/2 and Ag 3d5/2 peaks appear at 374.2 eV and 368.2 eV in

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Fig. 2b4 which is a result of the Ag diffusion to the surface (not only driven by

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annealing process but also the deposition temperature) [20, 28]. Apparently, the Ag 3d

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spectrum of the annealed samples has stronger peaks than as-deposited ones. The

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TEM and HRTEM images of the TiSiN/Ag coating are shown in Fig. 2(c-d). The discontinuous Ag layers and columnar crystals in TiSiN layers are distinct and agree

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well with the morphology in SEM images. Moreover, in HRTEM images, both the grains and amorphous phase are observed and the sizes of grains are about 20 – 30 nm. It can be deduced from HRTEM and XPS spectra that the TiSiN layer are mainly composed of nano-crystallites TiN and amorphous SiNx phases.

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Fig. 2 (a) The XRD patterns of the as-deposited and annealed TiSiN(/Ag) coatings (b) the XPS spectra of as-deposited and annealed TiSiN/Ag coatings (c-d) the multilayer structure of the TiSiN/Ag coating and micro-structure in TiSiN layer observed by HRTEM

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3.2 Corrosion and tribocorrosion properties

Fig. 3 (a-c) Bode and Nyquist plots of (annealed) TiSiN and TiSiN/Ag coatings in

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artificial seawater and (d-e) the corresponding equivalent electric circuits for coated and uncoated samples

To estimate the anti-corrosion performance of (annealed) TiSiN and TiSiN/Ag, EIS measurements were conducted and the results with the corresponding equivalent electric circuits are presented in Fig. 3. It is observed that annealing process can improve the protective capability (i.e. compactness) of the coatings. In the equivalent electric circuits, Rs, Rc, Ro and Rct correspond to the solution resistance, coating resistance, oxide resistance and charge transfer resistance, respectively. The constant phase element was used to evaluate the electric double layer on the interface of

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electrode and solution, which denotes capacitance characteristics when its exponent (n) is close to 1 (the parameter Qc, Qo and Qdl relate to coating, oxide and double layered capacitance). The deviation from pure capacitance is usually caused by the dispersion effect. Generally, the coating failure process can be roughly divided into three stages which are based on the process of the moisture reaching the coating/substrate

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interface. (i) The corrosive mediums have not reached the coating/substrate surface and it is expressed as one time constant. (ii) Corrosive ions contact with the oxidation

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film formed on the substrate due to a period of water penetration and thus two time

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constants are generated. (iii) The three time constants express as the corrosive ions

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continuing to go through the oxidation film and get in touch with the substrate. Three

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time constants were reflected in the bode-phase diagram (performed as three arcs in

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the curves shown in Fig. 3b). It is obvious that all of the samples including (annealed) TiSiN and TiSiN/Ag coatings express three time constants but as-deposited TiSiN and

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TiSiN/Ag coatings have a faster failure process which can be attributed to the existed pores in the coatings. For the substrate, the corrosive ions firstly have not reached the oxidation film (one time constant) and then go through oxidation film to get in touch with the substrate (two time constant). The porosity values of the TiSiN coatings before and after annealing are calculated according to Eq. 1 and polarisation resistance acquired from Fig. 4a. And the results are presented in Table 1 as well as the fitted Qc and Qdl. From the values of Qdl, it can come to a conclusion that although the corrosive ions go through the oxidation film and get in touch with the substrate, it still performance an excellent anti-corrosion property due to the relatively low value

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of the Qdl of substrate.

Table 1 Polarisation resistances (Rp) for the uncoated and coated samples and corresponding porosity values, and EIS fitting parameters for coating and double layered capacitance Impedance

Bare substrate

4.883

-

TiSiN

2.079

2.36

Annealed TiSiN

11.20

0.436

TiSiN/Ag

1.064

4.59

Annealed TiSiN/Ag

0.944

Qc (F)

n

Qdl (F)

n

-

-

5.02×10-5

0.88

3.844×10-5

0.60

7.39×10-4

0.74

3.38×10-6

0.76

2.48×10-10

0.8

7.37×10-8

0.93

3.32×10-4

0.78

1.01×10-7

0.92

1.22×10-5

0.82

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Porosity

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Rp(×107 Ω)

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5.17

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Polarisation

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It is observed that annealed TiSiN coating has a much smaller porosity than as-deposited coating while the porosity of TiSiN/Ag coating do not reduce after annealing process due to the Ag diffusion[28, 29]. The decrease of the porosity in TiSiN coating by annealing process can be attributed to a vacancy diffusion model and the grains growth.[30-32] And value difference in the coating and double layered capacitance between annealed and as-deposited samples indicates a slower penetration rate for corrosive mediums in annealed coatings. In general, annealing process can make the TiSiN coating densified accompanied by the porosity reducing and improved coatings can prevent corrosive mediums to contact with the substrate

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for a longer term.

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Fig. 4 Polarization curves of (annealed) TiSiN and TiSiN/Ag coatings (a) without and

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(b) with sliding (c) Corrosion current of samples with and without sliding (d) Wear rates and COF of samples

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Fig. 5 The LSCM wear tracks images along with the corresponding SEM images of (a)

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substrate (b-c) as-deposited and annealed TiSiN (d-e) as-deposited and annealed TiSiN/Ag

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Table 2 The corrosion potential (Ecorr) and corrosion current density (Icorr) obtained

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from potentiodynamic polarization curves Ecorr (V)

Icorr (*10-7A)

Samples

Static

During

Static

During

polarization tribocorrosion polarization tribocorrosion

Substrate

-0.363

-0.666

2.68

93.72

TiSiN

-0.233

-0.193

4.74

13.47

Annealed TiSiN

-0.298

-0.228

2.78

14.22

TiSiN/Ag

-0.358

-0.426

35.89

15.33

Annealed TiSiN/Ag

-0.312

-0.331

32.24

11.47

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Fig. 4a-b shows polarization curves of the (annealed) TiSiN and TiSiN/Ag coatings under static corrosion and sliding conditions in artificial seawater. The corrosion currents for specimens tested are given in Fig. 4c and Table 2. Ti6Al4V substrates exhibited the lowest current in the static corrosion due to the formation of oxidation film[33, 34]. Nevertheless, the oxidation film has the poor resistance to the friction so

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the corrosive current is particular high in dynamic corrosion which is in accordance with the previous researches [35-37]. The coated samples have more stable properties

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than bare substrate which indicated that the coating can protect the substrate

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especially during sliding process. In static corrosion, TiSiN coatings exhibit the best

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corrosion resistance and have quite low corrosion currents. But the passivation film

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formed on the surface would be damaged at a high potential. On the contrary, Ag

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doped coatings have the highest corrosion current in static corrosion. The situation is quite different in dynamic corrosion. The corrosion currents of substrates and

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(annealed) TiSiN coatings rise rapidly while the corrosion currents of TiSiN/Ag coatings decline apparently. The dynamics corrosion properties can be analyzed combined with wear rates and COF (shown in Fig. 4d). Particularly, the substrate is damaged severely during sliding process whose corrosion current and wear rate can reach to 9.4 × 10-6 A and 246 × 10-6 mm3N-1m-1. On the other hand, the LSCM wear tracks images along with the corresponding SEM images are shown in the Fig. 5. The differences among the sizes of the wear tracks indicates the annealed TiSiN/Ag multilayer coating had the minimum wear volume. In this section, annealing has a great effect on the results of COF which can be explained by stress relief in the

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coating (proved by the XRD results below) and annealed TiSiN/Ag coating exhibits the best anti-corrosion property (the lowest corrosion current, COF and wear rates). It is expected that Ag plays an important role in the tribocorrosion tests and it can be attributed to Ag lubricating and Ag+ releasing accompanied by Ag containing compounds creating as passive films (agree well with the Raman spectra below).

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In order to study the stress relief in the coating after annealing, XRD was employed and the results are presented in Fig. 6. Due to the negative stress values, it

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exhibits compressive stress in all coatings. As-deposited coatings have a higher

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residual stress than annealed ones which indicated that the annealing process can

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release the stress in the coatings [18, 19]and this is the reason why the annealed

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coatings have the lower COF than as-deposited ones[38-40].

Fig. 6 Residual stress with fitted line of (a-b) as-deposited and (c-d) annealed coatings measured by XRD The wear tracks after tribocorrosion tests as well as the as-deposited coatings are detected by Raman spectra (Fig. 7). For as-deposited coatings and substrate, two

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TiN peaks still exist in both coating spectra. But the spectra from 1400 – 1600 cm-1

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[44-47]are distinct between TiSiN and TiSiN/Ag coatings and the apparent peaks are

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assumedly caused by the Ag containing compounds generated in artificial seawater.

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Fig. 7 The Raman spectra of the wear track, outside the wear track and as-deposited coatings

In general, the annealed TiSiN/Ag multilayer coatings have the best tribocorrosion properties and the schematic diagram is shown in Fig. 8. On the one hand, the annealing process can decrease the porosity of the TiSiN monolayer coatings to make the coatings compact which can prevent corrosive ions diffusing to the substrate. What’s more, this process can also release the stress in the coating which can lead to the reduction of friction coefficient. Ag layers were inserted in the coating as multilayer structure. Although the anti-corrosion properties of the multilayer coatings

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are not as well as TiSiN monolayer coatings, the multilayer coatings have the best tribocorrosion properties especially after annealing. Due to the lubrication of Ag, the multilayer coatings have the lower COF and wear rates than TiSiN coatings. Besides, it is observed that Ag containing compounds generated in wear track in artificial

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seawater.

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Fig. 8 The schematic diagram of the TiSiN(/Ag) coatings’ corrosion and tribocorrosion behaviors

4 Conclusion

In this work, TiSiN and TiSiN/Ag coatings were deposited by multi arc ion plating and annealed at 650 ℃ for 5 h. Due to the structure analysis, the coatings are made up by TiSiN and discontinuous Ag layers. The TiSiN layer is composed of TiN nano-crystallites and SiNx amorphous phase. It is found that the porosities of the coatings decreased after annealing. Annealed coatings had a slower failure process in corrosion tests compared to the as-deposited coatings. Annealed coatings also had the

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lower COF than as-deposited ones which can be attributed to the stress release during the annealing process. Moreover, the TiSiN/Ag coatings have lower corrosion currents during friction process compared to the static corrosion and it can be explained by the Ag containing compounds generated in the wear track as passive films (verified by Raman spectra). To sum up, the annealed TiSiN/Ag multilayer

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coatings have the best tribocorrosion behavior in this work. It provides a new guidance for researchers to design a coating with both lubrication and anti-corrosion

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properties and to find a balance between corrosion and tribocorrosion behavior.

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Acknowledgment

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This work was supported by the National Science Fund for Distinguished Young

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Scholars (Grant No. 51825505), the National Natural Science Foundation of China (51771221), Ningbo Major Special Projects of the Plan "Science and Technology

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Credit Author Statement Yebiao Zhu: Conceptualization, Methodology, Investigation, Data Curation, Writing Original Draft, Writing - Review & Editing, Visualization Minpeng Dong: Validation, Formal analysis Jinlong Li: Resources, Writing - Review & Editing, Supervision, Project administration, Funding acquisition Liping Wang: Methodology, Resources, Project administration, Funding acquisition

Journal Pre-proof Declaration of interests ☒ The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

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☐The authors declare the following financial interests/personal relationships which may be considered as potential competing interests:

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Highlights 1. During tribocorrosion process, TiSiN/Ag coatings have the lowest wear rates. 2. Annealing process had can reduce the residual stresses of the coatings. 3. Compared to static corrosion, the corrosive current of TiSiN/Ag decreased during tribocorrosion tests.