Ceramic Coatings Research Articles

Corrosion resistance analysis of Al2O3-TiO2 composite ceramic coatings on carbon steel pipe surfaces

This study investigates the corrosion resistance of Al2O3-TiO2 composite coatings reinforced with multi-walled carbon nanotubes (MWCNTs) on carbon steel pipe surfaces. Coatings were deposited using atmospheric plasma spraying (APS) and high velocity oxy-fuel (HVOF) techniques. Microstructural analysis revealed that HVOF-sprayed coatings exhibited denser and more homogeneous structures compared to APS-sprayed coatings. Electrochemical tests in 3.5 wt% NaCl solution showed that the HVOF-sprayed Al2O3-13 wt% TiO2-1.5 wt% MWCNT coating demonstrated the lowest corrosion current density of 7.6 × 10−9 A/cm2 and the most positive corrosion potential. Hot corrosion tests in a simulated boiler environment (500°C, 1000 h) revealed that this coating also exhibited minimal weight gain (0.9 mg/cm2) and thickness loss (2 μm). The corrosion rate of the optimal coating was 0.05 mm/year, significantly lower than the bare carbon steel (2.45 mm/year). XRD analysis of corroded samples showed that HVOF-sprayed coatings maintained their original phase composition without detectable substrate corrosion products. The superior corrosion resistance of the HVOF-sprayed Al2O3-13 wt% TiO2-1.5 wt% MWCNT coating is attributed to its optimized composition, dense microstructure, and the reinforcing effect of MWCNTs. These findings provide valuable insights for developing advanced coating solutions to mitigate corrosion-related challenges in the oil and gas industry and other harsh industrial environments.

High‐temperature thermal conductivity measurement of porous ceramic coatings with a high heat flux CO2 laser rig

AbstractYttrium‐stabilized zirconia (YSZ) plays a crucial role in thermal barrier coatings widely used to protect metallic components in gas turbine engines against high‐temperature combustion product gases and harsh environments. The thermal conductivity of these coatings is a critical parameter influencing the gas turbine design, performance, and service life. In this study, a laser temperature gradient method is utilized to measure the thermal conductivity of porous YSZ coatings. The method employs specialized laser energy delivery to create a one‐dimensional temperature gradient through the sample thickness, closely simulating the operational condition. This approach provides an effective, direct means to determine the thermal conductivity of high‐temperature heat‐resistant porous ceramic materials.

Oxidation and ablation resistance of (TiZrHf)C medium-entropy ceramic coating on C/C composite constructed in-situ at low temperature down to 900°C

The low-cost construction of ultra-high temperature high/medium-entropy ceramic coatings is pivotal for advancing their engineering applications. The study successfully prepared (TiZrHf)C medium-entropy ceramic coatings on C/C composite surfaces using an in-situ molten salt disproportionation reaction at temperatures as low as 900°C. The (TiZrHf)C coatings, approximately 20 μm thick, showed uniform distribution of Ti, Zr, and Hf, typical of medium-entropy ceramics. The process entails Hf reducing Zr⁴⁺ and Ti⁴⁺ to divalent states, which then disproportionate and react with carbon to form the coatings. High-temperature oxidation tests revealed larger oxide grain sizes and dense boundaries in coatings with higher Ti content, indicating superior oxidation resistance. Additionally, ablation tests demonstrated that a suitable amount of liquid-phase TiO₂ formed on the composite surface improves ablation resistance by stabilizing the oxide layer. This cost-effective, highly designable method promotes medium/high-entropy ultra-high temperature ceramics' engineering application.

Roles of modified additives in the repair of damaged SiC-ZrB2/SiC coating of carbon/carbon composites

Damaged SiC-ZrB2/SiC (SZS) coatings of carbon/carbon (C/C) composites were repaired using polysiloxane (PSO)-based repair agents. SiC-ZrB2 powder was used as an inert filler, and Al2O3 and isopropyl alcohol (IPA) were introduced as modified additives. The effects of each component of the repair agents on the chemical composition, microstructure, and oxidation behavior of the repaired coatings were investigated, and the repair mechanism was clarified. The repaired area was dense and smooth, showed good compatibility with the original coating, and remained intact after oxidation at 1500 ℃ for 360 min. The addition of Al2O3 promoted the pyrolysis of PSO and formation of β-SiC, which was beneficial to the densification and oxidation resistance of the repaired coatings. The introduction of IPA improved the fluidity of the repair agents, and the repair agents infiltrated the coated C/C composites through the micropores on the damaged surface under capillary action, thereby enhancing the interfacial bonding strength. The weight loss of the damaged coating after oxidation decreased from 21.16 % to 0.48 % after repair. This work offers an approach for optimizing the repair of Si-based ceramic coatings.

Improving bond strength and deposition efficiency of ceramic coatings via low pressure cold spraying: A study on hydroxyapatite coatings with Cu-Zn blends

This study presents Low Pressure Cold Spraying (LPCS) method for ceramic coatings, aimed at enhancing efficiency and elucidating bonding mechanisms. It focuses on the deposition of ceramic coatings using LPCS, with hydroxyapatite (HA) on 316L stainless steel (SS) as an illustrative example. Despite the advantages of LPCS, retaining HA particles has proven challenging, resulting in thin coatings (11.09 ± 2.56 μm) with low bonding strength (1.80 ± 0.19 MPa). To address this issue, a composite coating strategy was developed by blending 20 wt% Cu and Zn powder with 80 wt% HA. This approach significantly improved coating properties, achieving enhanced bonding strength (33.70 ± 1.13 MPa), deposition efficiency (27 %), and hardness (136.30 ± 2.45 HV) compared to pure Cu-Zn coatings. Numerical simulations were conducted to interpret these experimental results, indicating that blending metal with HA improves deposition efficiency, bonding strength, and hardness. In HA coatings, particles fragment into submicron grains and embed into the substrate through mechanical interlocking (MI), with shockwave-induced bonding strengthening subsequent layers. For Cu-Zn coatings, bonding occurs through MI and adiabatic shear instability (ASI). In HA-Cu-Zn coatings, high-velocity HA particles and Zn particles enhance bonding further through in-situ tamping.

Advancing micromechanical property characterization in ceramic multilayer coatings via hierarchical machine learning

Advancing micromechanical property characterization in ceramic multilayer coatings via hierarchical machine learning

Evaluation of wear and corrosion resistance in acidic and chloride solutions of Cathodic Arc PVD chromium nitride coatings on untreated and plasma nitrided AISI 4140 steel

Chromium nitride ceramic like coatings are well known for their hardness and wear resistance, especially under severe conditions. When deposited on mild steel, nitriding is required for such applications to create a gradient hardness profile and improve the coating adhesion and the system's mechanical properties. Corrosion resistance is also necessary since these chromium coatings are recommended for applications in the plastic mould and injection industry. Therefore, in this work, the combination of a nitriding without white layer pretreatment and CrN coating was studied in a chloride and an acidic electrolyte, to asses if the diffusion layer also plays an important role as a corrosion protection treatment. Coating microstructure, adhesion to both nitrided and non-nitrided steel, wear resistance, and corrosion resistance in chloride and acidic media were evaluated. For comparison, bare and nitrided steel were also examined. Results indicated an improvement in the adhesion for the duplex treatment (nitriding + CrN). The CrN coating demonstrated a considerably lower coefficient of friction and wear rate compared to both non-nitrided and nitrided steel. Regarding corrosion, the iron nitride layer provides some protection in chloride environments; however, in acidic media, only the CrN coating plays a protective role. In both media, localized attack occurred at sites where the coating had defects, such as pores or pinholes through which the electrolyte comes into contact with the substrate. The duplex treatment proved to be the most effective surface treatment for AISI 4140, achieving excellent tribological properties, good adhesion, and high corrosion resistance in both neutral chloride and acidic solutions.

Enhancing wind turbine blade protection: Solid particle erosion resistant ceramic oxides-reinforced epoxy coatings

Wind energy has been regarded as one of the renewable energy sources to rely on in the future. In this aspect, wind turbine blade maintenance is quite a challenge in tropical areas like India. One of the main reasons why wind turbine blades get damaged and produce less energy is solid particle erosion. In the present work, nanocomposite epoxy (EP) coatings reinforced with Al2O3, ZrO2, and CeO2 nanoparticle fillers have been applied on glass fiber reinforced polymer (GFRP) substrates using a simple spray coating method. These nanoparticles have been prepared in-house by solution combustion synthesis (SCS) route using urea, glycine, and oxalyl dihydrazide fuels. X-ray diffraction, field emission scanning electron microscopy, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy have been used to characterize the materials and coatings. EP coatings with different Al2O3, ZrO2, and CeO2 nanoparticle concentrations have been subjected to solid particle erosion resistance tests at impinging angles of 30°, 60° and 90°. ZrO2 and CeO2 nanoparticle-reinforced EP coatings show better resistance to solid particle erosion than Al2O3-reinforced coatings. Estimated average erosion rates are 17 and 11.3 × 10−3 mm3 g−1, respectively, for epoxy coatings with 20 and 40 wt% ZrO2 nanoparticles. However, GFRP substrate and neat EP coating show much higher erosion rates with respect to nanoparticles-reinforced EP coatings. To ascertain a correlation between H3/E2 and the solid particle erosion rates of the coatings, nanoindentation tests have been carried out. Tensile strength and initial modulus of all the coatings are found to be directly proportional to the average erosion rates, whereas, elongation at break shows an inverse relationship with the average erosion rate. This correlation of mechanical properties with solid particle erosion performance can play a critical role in the development of realistic simulation of protective coatings for wind turbine blades.

Understanding the deposition of multilayered hydroxyapatite-bioactive glass/hydroxyapatite/titanium dioxide coatings on PEEK substrates by plasma spray

Poly-ether-ether-ketone (PEEK) is a polymeric material that is often used in biomedical applications due to its excellent mechanical properties and radiolucency; this material is, in general, biologically inert. In recent decades, thermally sprayed biocompatible coatings have been widely employed in metallic implants to improve the osseointegration process in the human body. Thus, not surprisingly, thermally sprayed biocompatible coatings can be envisaged as an excellent alternative to improve the material's surface properties. However, there is little information in the literature about the deposition of thermally sprayed bioactive coatings on polymeric substrates. In the present study, a titanium dioxide (TiO2) powder was plasma-sprayed on PEEK substrates acting as a bond coat to further deposition of hydroxyapatite (HA)/bioactive glass multilayered coatings. The design of experiments methodology was employed to produce coatings with tailored properties. A key aspect in this work is how the experiments were carried out to understand the effect of powder features, such as chemical composition, on the deposition of the ceramic coatings on the PEEK substrate. Heating/cooling physical laws were employed to discuss the results obtained. The methodology employed in this work allowed to deposit a multilayered coating with adhesion strength of about 50 MPa on PEEK substrates measured using scratch test. The coatings' structural, morphological, chemical, thermal, and mechanical evaluation was performed using X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy, differential scanning calorimetry, and micro indentation test, respectively. In-vitro tests were also performed on these coatings under static simulated conditions. The results show that the PEEK's surface can be successfully functionalized, turning it from showing an inert behavior to displaying bioactivity by applying a HA-based bilayer or multilayered coating.

A comparative study of TiO2, Ta2O5 and Nb2O5 coated Ti6Al4V titanium alloy for biomedical applications

Refractory metal oxides such as titanium dioxide (TiO2), tantalum oxide (Ta2O5), and niobium oxide (Nb2O5) coated-titanium and its alloys for medical applications have recently gained significant attention due to their remarkable properties, including high hardness, strong chemical inertness, and excellent biocompatibility. However, comparative studies among them remain scarce. In this study, thin films of Ta2O5, Nb2O5, and TiO2 were deposited on Ti6Al4V titanium alloy using radio frequency sputtering technology. Their properties were comparably evaluated through a series of tests, including scratching, nanoindentation, friction and wear, potentiodynamic polarization, and cell cultivation experiments. The results revealed that all three coatings, with a thickness of approximately 2.6–2.8 μm, exhibited an amorphous columnar growth pattern with dense surfaces resembling cauliflower. The bonding force of the TiO2 coating exceeds 50 N, which is 26.2 times and 14.5 times greater than that of Ta2O5 and Nb2O5, respectively. Furthermore, all coated samples demonstrate superior wear resistance, corrosion resistance, and biocompatibility compared to bare Ti6Al4V. Among the coatings, TiO2 showed the best performance, followed by Ta2O5, while Nb2O5 exhibited the least favorable performance. These findings revealed the performance differences among the three ceramic coatings on Ti6Al4V samples and offer valuable insights for further research and the selection of coatings to enhance the properties of Ti6Al4V titanium alloy for biomedical applications.

Enhanced thermal shock resistance of SiCf/SiC composites with Y-Al-Si-O glass ceramic environmental barrier coatings in water-oxygen conditions at 1350°C

In this study, Y-Al-Si-O(YAS) glass-ceramic environmental barrier coatings were prepared after modifying CVI-SiCf/SiC composites with microcrystalline glass. The resistance of both SiCf/SiC and SiCf/SiC with YAS-EBC to thermal shock was systematically examined using a water quenching method. The findings demonstrate that the SiCf/SiC composites with YAS-EBC exhibits outstanding thermal shock resistance. The coefficient of thermal expansion (CTE) of the YAS coating exhibits minimal deviation from that of SiCf/SiC and possesses a low modulus of elasticity. Upon experiencing thermal shock, the YAS coating is subjected to tensile stress, with an average thermal stress of merely ∼4.4 MPa. After undergoing 100 cycles, there was no evidence of debonding between the coating and the substrate, nor was a thermally grown oxide (TGO) layer observed at the interface. This research provides a credible method and theoretical foundation for enhancing the thermal shock resistance behavior of CVI-SiCf/SiC composites.

Microstructural and properties investigations of tantalum-doped tungsten diboride ceramic coatings via HiPIMS and RF magnetron sputtering

In this work, tantalum-doped tungsten boride ceramic coatings were deposited from a single sputtering target with the radio frequency (RF) and high-power impulse magnetron sputtering (HiPIMS) methods. Two-inch torus targets were synthesised from pure elements with the spark plasma sintering (SPS) method with a stoichiometric composition of W1-xTaxB2.5 (x = 0, 0.08, 0.16, 0.24). Films were deposited with RF and HiPIMS power suppliers at process temperatures from RT to 600 °C. The substrate heating and the energy of the ionised material impacting the substrate increase the surface diffusivity of adatoms and are crucial in the deposition process. The results of SEM and XRD investigations clearly show that the addition of tantalum also changes the microstructure of the deposited films. The coatings without tantalum possess a finer microstructure than those with 24% of tantalum. The structure of films is homogeneous along the film thickness and composed mainly of columns with a (0001) preferred orientation. Deposited coatings are composed mainly of P6/mmm α-WB2 structures. The analysis of nanoindentation results allowed us to determine that ceramic coatings obtained with the HiPIMS method possess hardness above 41 GPa and a ratio of hardness to reduced Young modulus above 0.1. The thickness of HiPIMS-deposited films is relatively small: only around 60% of the RF magnetron sputtered coatings even when the average power input was two times higher. However, it has been shown that the RF coatings require heating the substrate above 400 °C to obtain a crystalline structure, while the HiPIMS method allows for a reduction of the substrate temperature to 300 °C.

Processes and Properties of Self-Lubricating Coatings Fabricated on Light Alloys by Using Micro-Arc Oxidation: A Review

A self-lubricating coating is a kind of coating formed on the surface of the material by various processes that can self-replenish lubricating substances during the friction and wear process. This paper presents a comprehensive review of the processes and properties of self-lubricating ceramic coatings developed through Micro-arc Oxidation (MAO) on light alloys, including aluminum, magnesium, and titanium. Three technical approaches for the preparation of self-lubricating coatings via MAO are recapitulated. The structures and properties of the self-lubricating coatings prepared by each technical route are compared and analyzed, and the future development tendency of this field is also anticipated.

Suspension-Sprayed Calcium Phosphate Coatings with Antibacterial Properties.

Prosthesis loosening due to lack of osteointegration between an implant and surrounding bone tissue is one of the most common causes of implant failure. Further, bacterial contamination and biofilm formation onto implants represent a serious complication after surgery. The enhancement of osteointegration can be achieved by using bioconductive materials that promote biological responses in the body, stimulating bone growth and thus bonding to tissue. Through the incorporation of antibacterial substances in bioconductive, biodegradable calcium phosphate (CaP) coatings, faster osteointegration and bactericidal properties can be achieved. In this study, Cu-doped CaP supraparticles are spray-dried and suspension-sprayed CaP ceramic coatings with antibacterial properties are prepared using high-velocity suspension flame spraying (HVSFS). The objective was to increase the coatings' porosity and investigate which Cu-doped supraparticles have the strongest antibacterial properties when introduced into the coating layers. Biocompatibility was tested on human Osteosarcoma cells MG63. A porosity of at least 13% was achieved and the supraparticles could be implemented, enhancing it up to 16%. The results showed that the addition of Cu-doped supraparticles did not significantly reduce the number of viable cells compared to the Cu-free sample, demonstrating good biocompatibility. The antimicrobial activity was assessed against the bacterial strains Escherichia coli and Staphylococcus aureus, with Safe Airborne Antibacterial testing showing a significant reduction in both Gram-positive and Gram-negative strains on the Cu-doped coatings.

Microstructure and corrosion-resisting properties of CeO2-SiO2-Al2O3 composite coatings prepared by plasma electrolytic oxidation on aluminum matrix composites

CeO2-SiO2-Al2O3 composite coatings were prepared on aluminum matrix composites by plasma electrolytic oxidation in the electrolyte of a silicate system consisting of Na2SiO3 and NaOH. The effects of the content of the soluble salt additive Ce(NO3)3·6 H2O on the microstructure, elemental composition, phase structure, thickness, corrosion resistance, and resistance to high-temperature oxidation of the PEO coatings were systematically investigated. The results showed that the CeO2-SiO2-Al2O3 ternary composite ceramic coatings were prepared with the main components of the physical phases as α-Al2O3, γ-Al2O3, Al, and SiC. And the addition of Ce(NO3)3·6 H2O increased the thickness of the coatings from 14.75 μm to 82.71 μm. Meanwhile, densification showed a tendency to increase and then decrease with the concentration of Ce(NO3)3·6 H2O. The surface microscopic morphology of the PEO coatings was optimized with the increase of the added concentration when the Ce(NO3)3·6 H2O concentration was lower than 1.0 g/L, and the surface quality of the coatings deteriorated when the Ce(NO3)3·6 H2O concentration was higher than 1.0 g/L. The corrosion resistance of the coatings was improved when the concentration of Ce(NO3)3·6 H2O was increased to 82.71 μm by the electrochemical experiments and the cavitation experiments. The corrosion resistance of the coatings was optimized when the concentration of Ce(NO3)3·6 H2O was added at 1.0 g/L, the coating’s corrosion resistance was optimized.

Effect of Substrate Bias on the Structure and Tribological Performance of (AlTiVCrNb)CxNy Coatings Deposited via Graphite Co-Sputtering

In the existing literature, there are few studies on the effect of deposition bias on the tribological properties of carbon-doped high-entropy alloy coatings. In order to further study the effect of the deposition bias on the properties of coatings, (AlTiVCrNb)CxNy coatings were deposited via unbalanced RF magnetron sputtering. The microstructure and tribological properties of carbon-doped high-entropy alloy ceramic coatings under different deposition biases were studied. The composition, morphology, crystal structure, and chemical morphology of each element of the coating were analyzed using scanning electron microscopy (SEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The hardness, elastic modulus, friction, and wear properties of the coating were further characterized using a nanoindentation instrument, reciprocating sliding friction, a wear tester, and a white light interferometer. The coating density reached the optimal level when the deposition bias value was 90 V. The hardness and elastic modulus of the (AlTiVCrNb)CxNy coating increased first and then decreased with an increase in deposition bias, and the maximum hardness was 23.98 GPa. When the deposition bias was 90 V, the coating formed a good-quality carbon transfer film on the surface of the counterbody due to sp2 clusters during the friction and wear process. The average friction coefficient and wear rate of the (AlTiVCrNb)CxNy coating were the lowest, 0.185 and 1.6 × 10−7 mm3/N·m, respectively. The microstructure, mechanical properties, and tribological performance of the (AlTiVCrNb)CxNy coating were greatly affected by the change in deposition bias, and an (AlTiVCrNb)CxNy coating with excellent structure and friction properties could be prepared using graphite co-sputtering.

Efficient and Controllable Preparation of Super-Hydrophobic Alumina-Based Ceramics Coating on Aviation Al-Li Alloy Surface for Corrosion Resistance and Anti-Icing Behavior

Al-Li alloys have been widely applied in aircraft structural component and shell material. However, Al-Li alloys are prone to corrosion failure, which leads to a considerable safety risk in the aerospace field and greatly limits their industrial application. Herein, a simple, low-cost, and large-scale air-spraying technique is developed for the preparation of an alumina-based ceramics coating with enhanced corrosion resistance and anti-icing behavior. The results show that the static contact angle of the as-prepared coating is 157.2 ± 0.4°, and the rolling angle is only 9.8°, suggesting a super-hydrophobic surface. Meanwhile, the electrochemical corrosion potential of the coating is 70 mV higher than that of the substrate, and the corrosion current density of the coating also decreases by 1 order of magnitude, indicating a significantly improved corrosion resistance. In addition, the fabricated super-hydrophobic coating also shows excellent anti-pollution and anti-icing characteristics. This work provides positive guidance for expanding the application of hydrophobic coating in the aerospace industry, especially in some complex corrosion, icing, and pollution environments.

High‐temperature ablation resistance prediction of ceramic coatings using machine learning

AbstractSurface ablation temperature and linear ablation rate are two crucial indicators for ceramic coatings under ultrahigh temperatures service, yet the results collection of such two indicators in the process is difficult due to the long‐period material preparation and the high‐cost test. In this work, four kinds of machine learning models are applied to predict the above two indicators. The Random Forest (RF) model exhibits a high accuracy of 87% in predicting surface ablation temperature, while a low accuracy of 60% in linear ablation rate. To optimize the model, the novel features are constructed based on the original features by the sum of the importance weights in the model. Thereafter, the importance of the newly constructed features increases significantly, and the accuracy of the optimized RF model is improved by 11%, exceeding 70% in accuracy. By validation with available data and experiments, the optimized model demonstrates precise predictions of the target variables.

Evolution of microscopic domain structure and macroscopic properties of (1-x)(Bi0.5Na0.5)TiO3-xBaTiO3 ceramic coatings

Sodium bismuth titanate-based ferroelectric materials have a promising application in modern microdevices due to their strong ferroelectricity and high Curie temperature. The domain structure plays a crucial role in the piezoelectric and ferroelectric properties of (1-x)(Bi0.5Na0.5)TiO3-xBaTiO3 ((1-x)BNT-xBT)(x=0, 0.06, 0.08, 0.10) ceramic coatings. In this paper, (1-x)BNT-xBT ceramic coatings were prepared by supersonic plasma spraying. Piezoresponse-force microscopy (PFM) was employed to gain insight into the microscopic domain evolution of (1-x)BNT-xBT ceramic coatings. Piezoelectric-force Microscopy (PFM) results show that the 0.92BNT-0.08BT ceramic coating exhibits relatively homogeneous striped domains and island domains, as well as a maximum amplitude response with an average amplitude intensity of 67.6 pm, which increases the localized piezoelectric response of the ceramic coating. The switching spectroscopy piezoelectric-force microscopy (SS-PFM) results show that the local piezoelectric coefficient (PRmax) of the 0.92BNT-0.08BT ceramic coating reaches 426.5 pm/V at 15 V, and the ferroelectric domains exhibit significant switching behavior. This study provides new ideas to further understand the relationship between microscopic electrical domains and macroscopic properties of these important lead-free piezoelectric ceramics.

Tailoring mechanical, microstructural and toughening characteristics of plasma-sprayed graphene-reinforced samarium niobate coatings for extreme environments

Thermal barrier coatings (TBCs) are advanced ceramic layers applied to metal components to provide insulation and protection against high temperatures in extreme operating environments. This study investigated the effects of graphene nanoplatelet (GNP) reinforcement on samarium niobate (SN: SmNbO4) TBCs for extreme environments. Four ceramic top coat compositions were plasma-sprayed onto Inconel 718 substrates: Yttria-stabilized zirconia (YSZ), SmNbO4 (SN), and SN reinforced with 1 and 1.5 wt% GNPs (SN-1GNP, SN-1.5GNP). The research examined microstructural characteristics, phase evolution, mechanical properties and toughening mechanisms. GNP reinforcement significantly improved coating density, with SN-1.5GNP reaching 97.4 ± 1.64% compared to 91.3 ± 1.69% for SN and 86.6 ± 1.47% for YSZ. Hardness and elastic modulus were enhanced by 86.38% and 57.91% for SN-1GNP, and 101.09% and 65.23% for SN-1.5GNP respectively. Moreover, fracture toughness experienced a significant increase from 1.86 ± 0.4 to 5.48 ± 0.7 MPa·m1/2, facilitated by toughening mechanisms, like splat bridging, GNP pull-out, crack arrest and ferroelastic domain switching. Additionally, the SN-1.5GNP coating exhibited a higher adhesion strength of 36.84 MPa, thereby leading to improved layer distribution and lesser chance of delamination. Compared to YSZ, these findings suggest that GNP-reinforced SN coatings offer enhanced performance for extreme environment applications.