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npj Materials Degradation volume 8, Article number: 85 (2024 ) Cite this article color coating machine
Plasma spray-physical vapor deposition (PS-PVD) is a promising third-generation thermal barrier coatings (TBCs) technique. Feather-like columnar TBCs with excellent strain tolerance and low thermal conductivity can be achieved using PS-PVD. However, molten CMAS (CaO–MgO–Al2O3–SiO2) can penetrate coatings and accelerate PS-PVD TBCs failure due to the feather-like columnar structure. Hence, a strategy is proposed to alleviate molten CMAS corrosion. The super-hydrophobicity structure is fabricated via laser texturing on the surface of PS-PVD TBCs to repel molten CMAS wetting and spreading. Then, a thin layer of the Al-film is deposited on the laser-textured surface. Next, the Al-modified layer is in situ synthesized after vacuum heat treatment, preventing the infiltration of molten CMAS into the TBCs and reducing the coating damage. The results show that the contact angle of laser textured and Al-modified PS-PVD TBCs (LT-Al) at room temperature increased from 12.3° to 168.8°. The wetting and spreading behavior of molten CMAS of as-sprayed (AS), laser textured (LT), and LT-Al coatings is observed in situ at 1230 °C for 1800 s. The LT-Al coatings exhibited excellent CMAS corrosion resistance, attributed to the laser-textured micro-nano structures and Al-modified layer protection. The findings may be an effective approach for solving the disadvantage of PS-PVD feather-like columnar structure TBCs.
Thermal barrier coatings (TBCs) applied on the surface of hot section components in a harsh environment can significantly improve operating temperatures and service life1,2,3,4. The aero engines are expected to work at higher temperatures due to an increasing demand for thrust–weight ratio5,6. Feather-like TBCs prepared by plasma sprayed-physical vapor deposition (PS-PVD) have attracted significant of attention worldwide, due to their excellent thermal cycle performance and low thermal conductivity7,8,9,10,11. The CMAS particles melt and adhere to the TBCs surface when the CMAS particles enter the turbine engine, penetrating the porous coating and leading to premature failure of TBCs. Therefore, molten CMAS corrosion challenges hot end parts of aero engines12,13.
To solve the problem, considerable approaches have been made to mitigate molten CMAS attacks on TBCs in the past decades, primarily focusing on the selection of material and the coating surface treatment. For the selection of material, the rare-earth pyrochlores and fluorites (such as Gd2Zr2O714,15,16,17, Ti2AlC18, and Hf6Ta2O1719) have potential in CMAS corrosion resistance for lower thermal conductivity and higher phase stability than YSZ coating. For the treatment of the coating surface, inhibiting the wetting and spreading of molten CMAS is an effective protective approach for improving the corrosion resistance of TBCs. Fan et al. found that YSZ coatings with smooth surfaces and healed voids after laser polishing exhibit superior molten salt resistance and significantly alleviate leaching or in-diffusion of elements20. Guo et al. found that laser-glazed YSZ TBCs can improve CMAS resistance because the laser-glazed layer highly resists melting penetration21,22. However, the laser glazing changes the coating structure, and the segmented cracks caused by the re-solidification of the coating after melting cannot be avoided, which cannot fundamentally solve the problem.
Previous investigations conducted by the researchers have shown that laser texturing effectively regulated the hydrophobicity of the TBC surface by adjusting scanning distance. Moreover, a hydrophobicity YSZ surface was achieved after laser texturing, where the contact angle of the surface increased to 151.8°23. In addition, Zhang et al. 24,25,26,27,28,29,30,31 have proved that Al-deposited TBCs after vacuum heat treatment have superior CMAS corrosion resistance than the as-sprayed (AS) coatings. The improved resistance can be attributed to a protective overlayer synthesized in situ through the reaction of the deposited Al film with YSZ coating during vacuum heat treatment. Additionally, the micro-voids on the surface of TBCs can be healed after Al-modification. The protective overlayer and healed voids can effectively alleviate the penetration of molten CMAS, ensuring superior corrosion resistance of the Al-modified TBCs.
Inspired by this, a new CMAS corrosion resistance strategy is proposed in this paper. Firstly, a superhydrophobic surface is textured by a femtosecond laser. Then, an Al film is deposited on the textured surface. Subsequently, the samples are subjected to vacuum heat treatment, forming an Al-modified protective layer through the reaction of the deposited Al film with YSZ coating. The wetting and spreading behavior of CMAS on different surfaces has been investigated in detail. The corrosion resistance mechanisms of textured and Al-modified TBCs are elucidated.
The main reason that the hot end components of aircraft engines can work stably in harsh environments is the protective effect of TBCs. The CMAS corrosion, which mainly comes from atmospheric dust, sand, high-altitude volcanic ash, and dust inhaled from the ground during the engine start-stop stage, is a major problem for TBCs, especially for high-altitude volcanic ash, as shown in Fig. 1. According to Fig. 1a, the volcanic ash was inhaled into the aero-engine and quickly melted in high temperature. Then, the molten CMAS is deposited on the turbine blade surface, as shown in Fig. 1b, c. With time, the part of TBCs deposited on blades was peeled off due to thermochemical and thermomechanical attacks (Fig. 1d, e), leading to premature failure of TBCs. In a high-temperature environment, the molten CMAS infiltrated into the gaps of TBCs, causing a loss of strain tolerance and delaminating TBCs; consequently, the thermomechanical attack occurred. Additionally, the reaction of molten CMAS with 7YSZ resulted in the depletion of the Y2O3 stabilizer, causing a transition from the tetragonal metastable T’ phase to the monoclinic m phase. Then, the thermochemical attack happened.
a Airplane flew through the volcanic ash. b, c Deposition of molten CMAS on the surface of turbine blade TBCs (macro and micro images). d, e Spallation of turbine blade TBCs corroded by molten CMAS (macro and micro images).
Lotus leaf is characterized by super-hydrophobic properties and self-cleaning effect due to its hierarchically micro-nanostructured surface, as shown in Fig. 2a. Feather-like structured TBCs (Fig. 2b) fabricated by PS-PVD have attracted significant attention due to their excellent properties, such as high thermal cycle performance and low thermal conductivity. Moreover, PS-PVD TBCs have better resistance to molten CMAS wettability than APS TBCs27.
a Superhydrophobic lotus leaf and its microstructure - the source of inspiration. b PS-PVD TBCs preparation. c constructing the lotus leaf structure on PS-PVD TBCs surface. d Schematic diagram of femtosecond laser processing system and fabrication of micro-nanostructured PS-PVD TBCs. e Al film deposition by magnetron sputtering. f In situ synthesis of Al-modified layer on laser textured PS-PVD TBCs by vacuum heat treatment.
In the previous work conducted by the authors, the superhydrophobic surfaces based on lotus leaf have been manufactured via femtosecond laser texture on atmospheric plasma spraying TBCs, which exhibited a high contact angle (>150°)23 Such biomimetic microstructures were also introduced into PS-PVD TBCs to improve their molten CMAS resistance at high temperatures, as shown in Fig. 1c. The biomimetic microstructures were fabricated via optimized laser processing parameters. The processing parameters are shown in Table 2. The biomimetic microstructures comprising periodic cones and cauliflower were obtained by adjusting the scanning distance shown in Fig. 2c and maintaining other processing parameters constant. The PS-PVD TBC samples were manufactured via a self-built laser processing system, as shown in Fig. 2d.
The gaps between feature-like columnar structures are fatal defects for PS-PVD TBCs because molten CMAS can penetrate the coating quickly at capillary force, resulting in PS-PVD TBCs spalling failure. Therefore, a new anti-CMAS corrosion strategy for PS-PVD TBCs was proposed. The biomimetic microstructures were obtained by femtosecond laser texture. Subsequently, an Al film was deposited on the textured TBCs to heal the columnar gaps. Finally, the samples deposited with Al film were subjected to vacuum heat treatment, forming a dense Al-modified layer on the surface of textured PS-PVD TBCs. The effect of the Al-modified layer against molten CMAS corrosion is detailed in “The mechanisms of bionic structured TBCs restricting molten CMAS wetting” section, Fig. 9c.
Figure 3 shows the SEM images of the surface microstructure of each sample. Figure 3a–d depicts the morphology of PS-PVD TBCs AS surface. The PS-PVD TBCs surface is a rough surface similar to a cauliflower head, which is determined by the PS-PVD TBCs preparation process. The nanoparticles on the surface of the coating can also be found in Fig. 3d due to the vapor deposition of the PS-PVD method.
a–d AS coatings. e–h LT coatings. i–l LT-Al coatings.
Figure 3e–h shows the morphology of surfaces textured by femtosecond laser on PS-PVD TBCs. The coating material was ablated and removed by a laser beam to form a microgroove; the coating not removed formed the periodic block surface. Many defects (Fig. 3e, f) and non-melted particles (Fig. 3h) were exposed after laser processing due to the columnar gaps in PS-PVD TBCs. The molten CMAS penetrated the coating through these defects at high temperatures, accelerating the coating peeling failure. Therefore, the Al film was deposited on the textured surface, and an Al-modified layer was formed after vacuum heat treatment.
Figure 3i–l shows the SEM images of LT-Al coatings. According to Fig. 3j, k, the periodic block became a cone array, and defects disappeared, indicating that the defects exposed after laser processing were healed by Al film deposition and vacuum heat treatment. In addition, further evolution of the PS-PVD TBCs surface occurred after vacuum heat treatment. The aluminum film reacted with the 7YSZ in situ to form a homogeneous Al-modified layer and micro-nano papillae structure surface (Fig. 3l). The combination of micro-nano structure and periodic cone array results in the superhydrophobic properties of the PS-PVD TBCs, which will be discussed in Fig. 5 in the section “Superdyophobic properties of laser textured coatings”.
Figure 4a shows the cross-sectional SEM images of Al-deposited TBCs after laser processing. The higher magnification SEM image (see Fig. 4b) reveals that the Al film, approximately 5 μm thick with obvious contrast, is uniformly deposited on the coating surface. The distribution of the corresponding elements of the coatings can be seen in Fig. 4e–h. Figure 4c, d depicts the SEM images of the Al-deposited TBCs after vacuum heat treatment. The contrast of Al film disappeared, whereas the cone surface was covered with a micro-mastoid structure, corresponding to the SEM surface shown in Fig. 3l and indicating that the aluminum film reacted with the coating during vacuum heat treatment. The Al reacted with ZrO2 in the coating, forming an α-Al2O3 overlayer as follows:
a, b Al film deposited on laser textured coatings. e–h The corresponding element distribution mapping of (b). c, d Al film deposition images after vacuum heating treatment. i–l The corresponding element distribution mapping of (d).
First, the Zr generated in reaction (1) when Al reacted with ZrO2, then the Zr will further react with the remaining Al generating Al3Zr phase, which further explains why only a small amount of a-Al2O3 phase is observed additionally in Al-modified PS-PVD 7YSZ TBCs32. A comparison of Fig. 4e–h, k, l reveals that the Al film became thinner but more uniform, demonstrating that Al film changed to a liquid state and penetrated TBCs. This claim can be proven by Fig. 4g, k. There is virtually no oxygen element in the Al film overlayer in Fig. 4h, while an obvious distribution of oxygen elements can be observed in the Al-modified coating in Fig. 4l. The change in the oxygen element (Fig. 4h, l) further supports the reaction of Eq. (1). The generation of α-Al2O3 overlayer acts as a diffusion barrier for repelling the spreading and infiltration of molten CMAS in a high-temperature environment.
Static contact angle measurement was conducted on each sample to test for hydrophobicity at room temperature, as shown in Fig. 5. The AS coatings exhibit a hydrophilic property. The measured contact angle is 12.3° (Fig. 5a–c). The results in Fig. 5d–f indicate that the LT coatings are superhydrophobic, and the contact angle of the surface increases to 161.7°. The water droplets can move freely on the LT coatings due to their excellent superhydrophobic properties, similar to the water on the surface of the lotus leaf. Therefore, the water seems to dance on the surface of the textured coating (Video 1, Supporting Information). However, the AS coatings exhibit hydrophilic properties, and water droplets are wet and spread quickly on the surface of the coating (Video 2, Supporting Information).
a–c Hydrophilicity of AS coatings. d–f Super-hydrophobicity of LT coatings. g–i Super-hydrophobicity of LT-Al coatings.
According to Fig. 5g–i, the shape of a water droplet on the surface of the LT-Al coatings is approximately spherical, indicating a superhydrophobic surface. The contact angle increases to 168.8°, illustrating that the periodic cone array and Al-modified surface show the best superhydrophobic properties. The adhesion between the droplet and the LT-Al surface was measured (shown in Video 3 in the Supporting Information). When the droplet touched the LT-Al surface, its shape changed under the force instead of spreading on the surface. When the droplet was removed, it was separated from the LT-Al surface due to its large surface tension. For AS coatings (shown in Video 4 in the Supporting Information), the droplet wets and spreads quickly when it contacts with AS coating surface. It can be concluded that LT-Al coatings show super-hydrophobic properties after laser texturing and Al-modification. Next, each sample’s hydrophilic and hydrophobic properties to molten CMAS at high temperatures will be investigated.
Figure 6 shows the wetting and spreading process of molten CMAS on each sample. The CMAS cylinder 3 mm in height and 3 mm in diameter was placed on the surface of each sample, which was heated to 1230 °C at a rate of 5 °C/min. The CMAS block was fully melted at 1230 °C, and the sessile drop method was used to evaluate the contact angle between the molten CMAS and coating. It can be found that the contact angle and baseline of molten CMAS on each sample surface at 1230 °C 0 s are almost the same (Fig. 6b, e, and h), indicating that the CMAS block has just completely melted and has not started to wet and spread. As time went on, the contact angle of molten CMAS on each sample surface changed significantly. According to Fig. 6c, the stable contact angle of molten CMAS on AS coatings is 49.9°, which is significantly lower compared with the initial state at 1230 °C 0 s. The contact angle of molten CMAS on LT coatings at 1230 °C 1800 s is 78.5°, as shown in Fig. 6f. The angle is improved compared to 49.9° on the original coatings, indicating that laser-textured structure for PS-PVD TBCs can improve CMAS corrosion resistance. The contact measurement result in Fig. 6i shows the largest contact angle, reaching 99°. This angle is approximately two times higher than the AS coatings, indicating excellent thermal stability of the textured microstructure. The wetting process is a spontaneous spreading phenomenon of molten CMAS on coatings. The average spreading velocity of the wetting process at 1230 °C from 0 s to 1800 s was selected to describe the average wetting rate ν (mm/min), which is defined as:
where dIP and dSP are the diameters of the contact area of molten CMAS with coatings 0 s (initial phase) and 1800 s (stabilization phase) at 1230 °C, respectively. Parameter Δt is the interval between the initial and stabilization phases (0–1800 s). The spreading velocity of molten CMAS on AS, LT, and LT-Al coatings is 4.12 mm/h, 2.38 mm/h, and 1.29 mm/h, respectively. The spreading velocity of molten CMAS on AS coatings is more than twice that of molten CMAS on LT-Al coatings, leading to a rapid failure of AS coatings. It can be concluded that LT-Al coatings with the microstructure arrays fabricated by femtosecond laser can improve the hydrophobic property and repel the wetting and spreading of molten CMAS.
a–c Contact angle changes of molten CMAS on AS coatings. d–f Contact angle changes of molten CMAS on LT coatings. g–i Contact angle changes of molten CMAS on LT-Al coatings.
Figure 7 shows the cross-sectional images of AS coatings after wetting for 1800 s. The microstructure of the top of the coating was completely corroded and spalled due to the intense thermochemical reaction of CMAS with 7YSZ coating in Fig. 7a–d. According to Fig. 7c, the molten CMAS penetrated the coating through the columnar gap, fracturing the PS-PVD columnar crystals, which can be confirmed by the elemental distribution mapping in Fig. 7e–h. It can be concluded that Al and Si are more likely to penetrate the interior of the coating and lead to the enrichment inside the coating in Fig. 7e, g. As shown in Fig. 7d, the columnar crystal structure was damaged to fine grains, indicating that many tetragonal YSZ grains entered the molten CMAS glass phase through dissolution and migration at high temperatures. Moreover, 7YSZ grains remained in the CMAS glass phase in a dispersed state when cooling to room temperature. Since molten CMAS easily corrodes the AS coatings, effective measures must be taken to protect the original TBCs.
a–d AS TBCs after wetting for 1800 s. e–h The corresponding element distribution mapping of (a).
Figure 8 shows the cross-sectional SEM images of the LT and LT-Al TBCs after wetting at 1230 °C for 1800 s. According to Fig. 8a, b, the LT coating was corroded, causing it to peel off. The corresponding elemental distribution mapping demonstrates that the molten CMAS has penetrated the coating, as shown in Fig. 8e, g. Compared to LT coatings in Fig. 8a, b, the LT-Al TBCs in Fig. 8c, d shows excellent CMAS corrosion resistance. The microstructure of the LT-Al coatings was well preserved, and the corresponding elemental distribution mapping (Fig. 8i–l) shows that the elements were prevented from penetrating by the dense Al-modified layer. This observation indicates that the Al-modified layer protected 7YSZ, preventing molten CMAS infiltration into the interior of LT-Al coatings.
a, b LT-Al coatings after wetting. e–h The corresponding element distribution mapping of (a). c, d LT-Al coatings after wetting. i–l The corresponding element distribution mapping of (d).
Several wetting models were selected to investigate the anti-wetting and spreading mechanism of LT and LT-Al coatings at room and high temperatures. The composite contact surfaces of LT and LT-Al coatings were compared, revealing that the Cassie–Baxter equation is more suitable.
where f1 and f2 are the fraction of liquid and gas on the solid surface, respectively, θ1 and θ2 are the intrinsic contact angles of the two interfaces, fs is the area fraction of convex parts in the composite contact surface, r is the roughness factor of the material surface, and θc is the intrinsic contact angle of the original surface.
As demonstrated in previous investigation23, the original surface does not form a microstructure to trap air (the value of fs is 1) for AS coatings. Therefore, Eq. (4) can be written as: cosθLT = rcosθc. Then, LT and LT-Al coatings surfaces can be expressed as Eqs. (5) and (6), respectively:
Room temperature is characterized by the following conditions: rcosθc=cos12.3°, θLT = 161.7° and θLT-Al = 168.8°. The corresponding area fraction of the LT and LT-Al coatings surfaces can be calculated by substituting these conditions into Eqs. (5) and (6). The values of fLT and fLT-Al are extremely small due to the superhydrophobic properties of LT and LT-Al coating surfaces, i.e., approximately 2.5% and 0.96%, respectively. The superhydrophobic mechanism of laser-textured YSZ surface at room temperature (reported in a previous study23) is derived from two reasons. The first one is the changes in chemical components during laser irradiation of TBC coatings, decreasing the surface polarity. The second one is the fabrication of micro-nano composite structures of TBC surface.
Compared with room temperature, the wetting mechanisms of molten CMAS on each sample are different when the temperature is 1230 °C, due to the thermochemical and thermomechanical effect of molten CMAS on TBCs. Figure 9a–c shows the high-temperature models of CMAS cylinders on AS, LT, and LT-Al coatings, respectively. As shown in Fig. 9a, the molten CMAS reacted with 7YSZ and penetrated the coating easily. Then, the molten CMAS spreads quickly, resulting in a minimum contact angle. The laser-textured structures delay the spread of molten CMAS for LT coatings in Fig. 9b. However, the diffusion of the element cannot be prevented. The laser-textured structures were gradually destroyed due to the reaction of molten CMAS with 7YSZ coatings.
a AS coatings. b LT coatings. c LT-Al coatings.
Figure 9c shows the high-temperature wetting model of CMAS on LT-Al coatings. The Al film resulted in a thin protective layer on the LT coating surface. The LT-Al coatings with an Al-modified layer can effectively hinder the thermal chemical reaction between the molten CMAS and 7YSZ coatings. Thus, the microstructures of the laser texture are well maintained to repel molten CMAS spreading. In addition, the existence of an Al-modified layer reduces the diffusion rate of elements into the coating. The above reasons explain how LT-Al coatings process excellent CMAS corrosion resistance and the largest contact angle. It can be concluded that the LT-Al coatings are a promising method for improving the CMAS resistance of PS-PVD TBCs by repelling wetting and prolonging infiltration time.
In this work, a new CMAS corrosion resistance strategy for LT-Al coating was proposed and tested at room and high temperatures. The LT-Al coatings mechanisms of wetting and CMAS corrosion resistance were investigated. The LT-Al coatings are characterized by excellent superhydrophobic characteristics after laser texturing and Al-modification; the contact angle on the surface of LT-Al coatings reached 168.8°. The LT-Al coatings can effectively impede the wetting and spreading of molten CMAS on its surface. Compared with AS coatings, the stable contact angle of molten CMAS on LT-Al coatings increased to 99° with a dwell time of 1800 s at 1230 °C. The anti-wetting mechanisms of LT-Al coatings at high temperatures can be attributed to two aspects: (i) the microstructure textured by femtosecond laser repels molten CMAS spreading and (ii) the Al-modified layer on the surface of LT-Al coatings mitigates the diffusion of molten CMAS into the PS-PVD TBCs.
The corrosion resistance peculiarities of LT-Al coating in this study would provide some meaningful references for the design or optimization of PS-PVD TBCs. Thus, from the engineering point of view, the LT-Al strategy is promising for enhancing the molten CMAS corrosion resistance of PS-PVD TBCs.
TBCs, including bond and topcoat ceramic coating, were deposited using a PS-PVD Multicoating System (Oerlikon Metco). The DZ40M superalloy with a thickness of 6 mm and diameter of 25.4 mm was used as the substrate. The substrate was grit-blasted and ultrasonically cleaned before deposition with gasoline and ethanol. The commercially available powder (NiCrAlY, Oerlikon-Metco, 15–45 μm) and 7YSZ powder (7 wt% Y2O3–ZrO2, 6700, Oerlikon-Metco, 1–30 μm) were used to prepare the bond and ceramic coatings, respectively. The bond coating and ceramic layer thickness were approximately 100 μm and 200 μm, respectively. The bond coating of samples was prepared via PS-PVD using the low-pressure plasma spraying mode. An O3CP gun with an input power of up to 180 kW was used for 7YSZ topcoat ceramic layer fabrication. The detailed spraying parameters are listed in Table 1.
An amplified Yb: KGW solid-state laser system (Pharos® Light Conversion Ltd, Vilnius, Lithuania) with a pulse width of 240 fs and a central wavelength of 1030 nm was used. The laser beam was vertically focused onto the sample surface using a two-axis galvanometer scanner (PS1XY2-S4, CTI Inc) with a focusing field lens (focal length, 170 mm). The maximum power is 20 W, and the focused spot diameter is 50 μm. The optimized laser texturing parameters are listed in Table 2.
Firstly, a metallic Al film was deposited on the surface of laser-textured PS-PVD TBCs via direct current circular magnetron sputtering (J-1250, Jinzhou Industrial Coating, China). The aluminum target (purity, 99.99%) was used for deposition; the direct current, voltage, and pressure were set at 3 A,150 V, and 5 × 10−3 Pa, respectively. The thickness of Al film deposited on the surface of coatings was approximately 5 μm. Subsequently, the Al-deposited samples were subjected to vacuum heat treatment at 608 °C for 1 h, 700 °C for 1 h, and 980 °C for 2 h separately. The Al film melted and infiltrated the porous PS-PVD TBCs during vacuum heat treatment. Then, the open pores and columnar gaps in TBCs were filled with molten aluminum, and a dense layer was formed via an in situ synthesis reaction of Al and ZrO2. Finally, the laser-tailored and Al-modified structures were fabricated on the surface of PS-PVD TBCs.
The static contact angle of surfaces under room temperature was measured using an optical contact angle measurement instrument (Betop, DSA-X, China). The angle was measured on the samples to test for hydrophobicity using 3 μL deionized water droplets. The contact angle was measured by the Yong-Laplace equation for the droplet morphology on the sample surface.
The CMAS powders used in the study were composed of 2%CaO–21%MgO–17%Al2O3–42%SiO2, which has been detected by X-ray fluorescence. In addition, the glass transition temperature and melting peak were 1043 °C and 1200 °C, respectively.
High-temperature wettability was measured using a contact angle measurement system (Kruss, DSAHT, Germany). The CMAS powders were compacted into a cylinder with a diameter of 3 mm and a height of 3 mm onto the PS-PVD samples. Then, the CMAS cylinder and coating substrate assembly were placed on the holder and carefully moved into the tube furnace. The previous experimental work shows that the CMAS cylinder can fully melt at 1230 °C. Therefore, the substrate and CMAS in the furnace were heated to 1230 °C in the atmosphere environment at a rate of 5 °C/min with a dwelling time of 1800 s in the atmosphere environment. The wetting and spreading changes of the CAMS cylinder were observed and recorded using analysis software (Kruss ADVANCE, Germany).
The static contact angle of surfaces under room temperature was measured using an optical contact angle instrument (Betop, DSA-X, China) and 3 μL deionized water droplets. Different samples’ surface and cross-sectional microstructures before and after testing were characterized by a cold field emission scanning electron microscope (Hitachi, SU8220, Japan) equipped with energy-dispersive X-ray spectroscopy.
The data that support the findings of this study are available from the corresponding author upon reasonable request. Correspondence and requests for materials should be addressed to Z.J. Fan and X.F. Zhang.
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We would like to acknowledge the financial support from the National Key R&D Program of China (2023YFB4605900), the National Natural Science Foundation of China (52322104, 52172067, and 92160202), the Natural Science Foundation of Guangdong Province (2021B1515020038), the Guangdong Special Support Program (2019BT02C629), the Guangdong Provincial Science and Technology Program (2023A0505010017), the Science Center for Gas Turbine Project (P2023-C-IV-002-001), the Key Research and Development Projects in Shaanxi Province (2019ZDLGY01-07).
State Key Laboratory for Manufacturing Systems Engineering, Xi’an Jiaotong University, Xi’an, 710054, China
Xueshi Zhuo, Xiaomao Sun, Peng Shen, Xuesong Mei, Jianlei Cui & Zhengjie Fan
Institute of New Materials, Guangdong Academy of Sciences, Guangzhou, 510650, China
Xueshi Zhuo, Jian Wu, Hao Dong & Xiaofeng Zhang
Guangdong Provincial Key Laboratory of Modern Surface Engineering Technology, Guangzhou, 510650, China
Xueshi Zhuo, Jian Wu, Hao Dong & Xiaofeng Zhang
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X.Z. and X.S. conducted experimental studies and analyzed the data. J.W., D.H., and P.S. conducted the experiments. X.M., J.C., Z.F., and X.Z. contributed to the discussion of the results. X.Z. and Z.F. are co-first authors of this work.
Correspondence to Xiaofeng Zhang or Zhengjie Fan.
The authors declare no competing interests.
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Zhuo, X., Sun, X., Wu, J. et al. Molten CMAS resistance strategy for PS-PVD TBCs based on laser textured and Al-modified bionic structure. npj Mater Degrad 8, 85 (2024). https://doi.org/10.1038/s41529-024-00505-2
DOI: https://doi.org/10.1038/s41529-024-00505-2
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