Surface & Coatings Technology最新文献_第4页

Fabrication of hydrophobic corrosion-resistant microarc oxidation titanium alloy through pore-sealing treatment with secondary growth of ZIF-8 seed crystals

IF 5.3 2区材料科学 Q1 MATERIALS SCIENCE, COATINGS & FILMS

Surface & Coatings Technology

Pub Date : 2025-02-10 DOI: 10.1016/j.surfcoat.2025.131898

Lei Wu , Qiuyan Ye , Kun Zhang , Xiaoyan Guo , Jiaqiao Li , Yongnan Chen , Fan Fang , Hantao Chang

The inherent porous structure of Micro-arc oxidation (MAO) coatings may facilitate penetration of corrosive ions into the substrate, thereby compromising its corrosion resistance. In this work, the metal-organic framework (MOF) ZIF-8 was employed to seal the micropores in the MAO coating of titanium alloy (MAO-Ti) through a secondary growth method involved initially physically pre-loading crystal seeds into the micropores, followed by solvent thermal synthesis. Consequently, an excellent cohesive pore-sealing coating known as ZIF-8@MAO was successfully developed. The anchoring effect between ZIF-8 in the micropores and the substrate forms a solid blocking layer, which can effectively avoid the issue of traditional sealing layers detaching easily. Additionally, the arranged ZIF-8 crystals on the surface of MAO-Ti imparts excellent hydrophobicity and high stability to the alloy, evidenced by contact angle tests conducted under various solution environments, where the water contact angles (WCAs) exceeded 140°. Moreover, ZIF-8 microcrystals act as effective sealants for the micropores of MAO-Ti, effectively safeguarding the internal titanium alloy matrix against chloride ion infiltration and ensuring long-term corrosion resistance. Electrochemical tests assessing the corrosion resistance of the coatings revealed a significant improvement in the corrosion resistance of the ZIF-8@MAO pore-sealing coating compared to the primary MAO-Ti coating. The charge transfer resistance (R_ct) increased from 2.05 × 10⁴ Ω/cm² to 1.287 × 10⁹ Ω/cm², while the current density (I_corr) declined from 2.03 × 10⁻⁸ A/cm² to 2.65 × 10⁻¹³ A/cm².

{"title":"Fabrication of hydrophobic corrosion-resistant microarc oxidation titanium alloy through pore-sealing treatment with secondary growth of ZIF-8 seed crystals","authors":"Lei Wu , Qiuyan Ye , Kun Zhang , Xiaoyan Guo , Jiaqiao Li , Yongnan Chen , Fan Fang , Hantao Chang","doi":"10.1016/j.surfcoat.2025.131898","DOIUrl":"10.1016/j.surfcoat.2025.131898","url":null,"abstract":"<div><div>The inherent porous structure of Micro-arc oxidation (MAO) coatings may facilitate penetration of corrosive ions into the substrate, thereby compromising its corrosion resistance. In this work, the metal-organic framework (MOF) ZIF-8 was employed to seal the micropores in the MAO coating of titanium alloy (MAO-Ti) through a secondary growth method involved initially physically pre-loading crystal seeds into the micropores, followed by solvent thermal synthesis. Consequently, an excellent cohesive pore-sealing coating known as ZIF-8@MAO was successfully developed. The anchoring effect between ZIF-8 in the micropores and the substrate forms a solid blocking layer, which can effectively avoid the issue of traditional sealing layers detaching easily. Additionally, the arranged ZIF-8 crystals on the surface of MAO-Ti imparts excellent hydrophobicity and high stability to the alloy, evidenced by contact angle tests conducted under various solution environments, where the water contact angles (WCAs) exceeded 140°. Moreover, ZIF-8 microcrystals act as effective sealants for the micropores of MAO-Ti, effectively safeguarding the internal titanium alloy matrix against chloride ion infiltration and ensuring long-term corrosion resistance. Electrochemical tests assessing the corrosion resistance of the coatings revealed a significant improvement in the corrosion resistance of the ZIF-8@MAO pore-sealing coating compared to the primary MAO-Ti coating. The charge transfer resistance (<em>R</em><sub>ct</sub>) increased from 2.05 × 10<sup>4</sup> Ω/cm<sup>2</sup> to 1.287 × 10<sup>9</sup> Ω/cm<sup>2</sup>, while the current density (<em>I</em><sub>corr</sub>) declined from 2.03 × 10<sup>−8</sup> A/cm<sup>2</sup> to 2.65 × 10<sup>−13</sup> A/cm<sup>2</sup>.</div></div>","PeriodicalId":22009,"journal":{"name":"Surface & Coatings Technology","volume":"501 ","pages":"Article 131898"},"PeriodicalIF":5.3,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143437073","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Production of NO in nitrogen-based active screen plasma nitriding devices, a disadvantage or an opportunity?

IF 5.3 2区材料科学 Q1 MATERIALS SCIENCE, COATINGS & FILMS

Surface & Coatings Technology

Pub Date : 2025-02-10 DOI: 10.1016/j.surfcoat.2025.131896

T. Czerwiec , O. Carrivain , M. Masieiro , R. Hugon , C. Cardinaud , T. Belmonte , C. Noël , R.P. Cardoso , G. Marcos

Nitric oxide (NO) can have both negative and positive effects on life. Therefore, it is crucial to control its production and destruction, and plasmas associated with reactive surfaces can effectively serve these functions. In this study, we observed the emission of NO radical using optical emission spectroscopy during nitriding experiments in active screen plasma nitriding (ASPN) with pure nitrogen. This phenomenon can be attributed to the contamination of the nitriding reactor surfaces by water vapor when the reactor is opened to introduce the samples for treatment.

In N₂–20% H₂ plasmas, the emissions of both NO and iron are very low. However, when the hydrogen supply is cut off, we observed that, after a few minutes, the intensities of the NO and iron emission lines become comparable to those obtained when the plasma is generated in nitrogen alone.

We conducted GDOES and XPS characterizations of the surfaces of samples fixed on the grid and treated in both N₂ and N₂–10% H₂ plasmas under similar contamination conditions. The results showed that the grid is nitrided in the N₂-H₂ plasma mixture, while no nitriding occurs in pure nitrogen plasma. A substantial quantity of NO-containing compounds (nitrosonium and nitrite or nitrito species) is detected when the treatment is performed solely in nitrogen plasma.

We then discussed the production of NO and proposed a surface reaction between the active nitrogen species generated in the plasma and the iron oxide formed through surface segregation on the grid. This reduction reaction consumes active nitrogen, resulting in no nitriding of the grid. In N₂-H₂ plasmas, the active hydrogen reduces the oxides formed on the grid, allowing the active nitrogen to facilitate nitriding.

In N₂-H₂ mixtures, an oxynitride composed of the metallic elements of stainless steel forms on the surface, complicating the sputtering of iron in the compound regime. We also explored the potential for controlling the cleanliness of the plasma nitriding process and the possibility of fixing nitrogen through the production of NO.

{"title":"Production of NO in nitrogen-based active screen plasma nitriding devices, a disadvantage or an opportunity?","authors":"T. Czerwiec , O. Carrivain , M. Masieiro , R. Hugon , C. Cardinaud , T. Belmonte , C. Noël , R.P. Cardoso , G. Marcos","doi":"10.1016/j.surfcoat.2025.131896","DOIUrl":"10.1016/j.surfcoat.2025.131896","url":null,"abstract":"<div><div>Nitric oxide (NO) can have both negative and positive effects on life. Therefore, it is crucial to control its production and destruction, and plasmas associated with reactive surfaces can effectively serve these functions. In this study, we observed the emission of NO radical using optical emission spectroscopy during nitriding experiments in active screen plasma nitriding (ASPN) with pure nitrogen. This phenomenon can be attributed to the contamination of the nitriding reactor surfaces by water vapor when the reactor is opened to introduce the samples for treatment.</div><div>In N<sub>2</sub>–20% H<sub>2</sub> plasmas, the emissions of both NO and iron are very low. However, when the hydrogen supply is cut off, we observed that, after a few minutes, the intensities of the NO and iron emission lines become comparable to those obtained when the plasma is generated in nitrogen alone.</div><div>We conducted GDOES and XPS characterizations of the surfaces of samples fixed on the grid and treated in both N<sub>2</sub> and N<sub>2</sub>–10% H<sub>2</sub> plasmas under similar contamination conditions. The results showed that the grid is nitrided in the N<sub>2</sub>-H<sub>2</sub> plasma mixture, while no nitriding occurs in pure nitrogen plasma. A substantial quantity of NO-containing compounds (nitrosonium and nitrite or nitrito species) is detected when the treatment is performed solely in nitrogen plasma.</div><div>We then discussed the production of NO and proposed a surface reaction between the active nitrogen species generated in the plasma and the iron oxide formed through surface segregation on the grid. This reduction reaction consumes active nitrogen, resulting in no nitriding of the grid. In N<sub>2</sub>-H<sub>2</sub> plasmas, the active hydrogen reduces the oxides formed on the grid, allowing the active nitrogen to facilitate nitriding.</div><div>In N<sub>2</sub>-H<sub>2</sub> mixtures, an oxynitride composed of the metallic elements of stainless steel forms on the surface, complicating the sputtering of iron in the compound regime. We also explored the potential for controlling the cleanliness of the plasma nitriding process and the possibility of fixing nitrogen through the production of NO.</div></div>","PeriodicalId":22009,"journal":{"name":"Surface & Coatings Technology","volume":"500 ","pages":"Article 131896"},"PeriodicalIF":5.3,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143421195","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Enhancing joint strength in direct-injection-molded PPS-Ti composite through plasma electrolytic oxidation coated interfaces

IF 5.3 2区材料科学 Q1 MATERIALS SCIENCE, COATINGS & FILMS

Surface & Coatings Technology

Pub Date : 2025-02-07 DOI: 10.1016/j.surfcoat.2025.131893

Xin Lv , Weiping Dong , Yongwang Sheng , Jianfeng Jin , Mengjia Li , Yuan Zhao , Shiju E , Linlin Wang

This study investigates the enhancement of bonding strength between titanium alloy (Ti-6Al-4V) and polyphenylene sulfide (PPS) in injection molded direct joining (IMDJ) composite structures through a combined sand blasting and plasma electrolytic oxidation (PEO) method. The primary objective is to explore how surface modification, particularly the introduction of chemical functional groups, influences joint strength. A porous surface structure with both macro- and micro-scale features was created on the titanium alloy surface using the sand blasting and PEO process. Urea (CO(NH₂)₂) was added to the electrolyte to successfully introduce amino (-NH₂) and hydroxyl (-OH) groups onto the metal surface, which promote hydrogen bonding and σ-hole interactions with the PPS. The results showed that increasing the urea concentration led to a corresponding increase in -NH₂ and -OH group density on the metal surface. The maximum bonding strength was observed at a urea concentration of 6 g/L, where the bonding strength was 17 times higher than that of the sand blasting group and 2.4 times stronger than the group without urea addition. This enhancement is attributed to both mechanical interlocking and the formation of chemical bonds between the titanium alloy and PPS. The findings suggest that the combined sand blasting and PEO treatment is a highly effective and simple method to achieve high-strength, durable connections in metal-polymer composite structures, with significant implications for advanced manufacturing and materials design.

{"title":"Enhancing joint strength in direct-injection-molded PPS-Ti composite through plasma electrolytic oxidation coated interfaces","authors":"Xin Lv , Weiping Dong , Yongwang Sheng , Jianfeng Jin , Mengjia Li , Yuan Zhao , Shiju E , Linlin Wang","doi":"10.1016/j.surfcoat.2025.131893","DOIUrl":"10.1016/j.surfcoat.2025.131893","url":null,"abstract":"<div><div>This study investigates the enhancement of bonding strength between titanium alloy (Ti-6Al-4V) and polyphenylene sulfide (PPS) in injection molded direct joining (IMDJ) composite structures through a combined sand blasting and plasma electrolytic oxidation (PEO) method. The primary objective is to explore how surface modification, particularly the introduction of chemical functional groups, influences joint strength. A porous surface structure with both macro- and micro-scale features was created on the titanium alloy surface using the sand blasting and PEO process. Urea (CO(NH<sub>2</sub>)<sub>2</sub>) was added to the electrolyte to successfully introduce amino (-NH<sub>2</sub>) and hydroxyl (-OH) groups onto the metal surface, which promote hydrogen bonding and σ-hole interactions with the PPS. The results showed that increasing the urea concentration led to a corresponding increase in -NH<sub>2</sub> and -OH group density on the metal surface. The maximum bonding strength was observed at a urea concentration of 6 g/L, where the bonding strength was 17 times higher than that of the sand blasting group and 2.4 times stronger than the group without urea addition. This enhancement is attributed to both mechanical interlocking and the formation of chemical bonds between the titanium alloy and PPS. The findings suggest that the combined sand blasting and PEO treatment is a highly effective and simple method to achieve high-strength, durable connections in metal-polymer composite structures, with significant implications for advanced manufacturing and materials design.</div></div>","PeriodicalId":22009,"journal":{"name":"Surface & Coatings Technology","volume":"499 ","pages":"Article 131893"},"PeriodicalIF":5.3,"publicationDate":"2025-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143377588","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Phase evolution and microstructure of suspension HVOF-sprayed alumina coatings

IF 5.3 2区材料科学 Q1 MATERIALS SCIENCE, COATINGS & FILMS

Surface & Coatings Technology

Pub Date : 2025-02-06 DOI: 10.1016/j.surfcoat.2025.131885

Paul Junge , Eva M. Heppke , Rafael Kleba-Ehrhardt , David Karl , Grzegorz Cios , Christian Rupprecht

High-velocity oxygen fuel (HVOF) spraying enables the deposition of particulate ceramic materials, producing dense coatings in the micrometer to millimeter range that are particularly suitable for coating metallic parts for demanding environments. Alumina (Al₂O₃) is one of the most commonly used feedstocks for thermal spray coatings because it has good dielectric properties, excellent hardness, and corrosion resistance while being cost-effective. In this work, alumina coatings from two aqueous suspensions with different particle size distributions were processed by HVOF spraying. Rietveld refinements of the X-ray diffraction (XRD) data were used to quantitatively determine the phase content within the as-sprayed coatings. The phase composition was further explored using the electron backscatter diffraction (EBSD) method. Our work provides strong evidence for the higher retention of the thermodynamically stable α-

{Al}_{2} O_{3}

phase in suspension HVOF-sprayed coatings compared to the powder counterpart. In addition, the impact of key processing parameters was studied, providing guidance for the production of particular phase compositions and microstructures tailored to specific application requirements.

{"title":"Phase evolution and microstructure of suspension HVOF-sprayed alumina coatings","authors":"Paul Junge , Eva M. Heppke , Rafael Kleba-Ehrhardt , David Karl , Grzegorz Cios , Christian Rupprecht","doi":"10.1016/j.surfcoat.2025.131885","DOIUrl":"10.1016/j.surfcoat.2025.131885","url":null,"abstract":"<div><div>High-velocity oxygen fuel (HVOF) spraying enables the deposition of particulate ceramic materials, producing dense coatings in the micrometer to millimeter range that are particularly suitable for coating metallic parts for demanding environments. Alumina (Al<sub>2</sub>O<sub>3</sub>) is one of the most commonly used feedstocks for thermal spray coatings because it has good dielectric properties, excellent hardness, and corrosion resistance while being cost-effective. In this work, alumina coatings from two aqueous suspensions with different particle size distributions were processed by HVOF spraying. Rietveld refinements of the X-ray diffraction (XRD) data were used to quantitatively determine the phase content within the as-sprayed coatings. The phase composition was further explored using the electron backscatter diffraction (EBSD) method. Our work provides strong evidence for the higher retention of the thermodynamically stable <em>α</em>-<span><math><msub><mi>Al</mi><mn>2</mn></msub><msub><mi>O</mi><mn>3</mn></msub></math></span> phase in suspension HVOF-sprayed coatings compared to the powder counterpart. In addition, the impact of key processing parameters was studied, providing guidance for the production of particular phase compositions and microstructures tailored to specific application requirements.</div></div>","PeriodicalId":22009,"journal":{"name":"Surface & Coatings Technology","volume":"499 ","pages":"Article 131885"},"PeriodicalIF":5.3,"publicationDate":"2025-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143388184","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Exploring ionised metal flux fraction in magnetron sputtering: Insights from laboratory and industrial applications

IF 5.3 2区材料科学 Q1 MATERIALS SCIENCE, COATINGS & FILMS

Surface & Coatings Technology

Pub Date : 2025-02-06 DOI: 10.1016/j.surfcoat.2025.131866

Peter Klein , Jaroslav Hnilica , Vjačeslav Sochora , Petr Vašina

Magnetron sputtering is one of the cornerstones of thin film-forming methods. The literature provides excessive knowledge about inner plasma processes, deposition control and thin film growth, but the overwhelming majority reports on results conducted on a small lab scale. To transfer this knowledge and use it in industrial applications, one has to overcome many challenges, the most profound being scaling the process from the lab scale towards a large industrial scale. This paper explores the critical differences in deposition fluxes and ionisation of metals when scaling from lab to industrial systems. While in the laboratory, the direct current magnetron sputtering does not create sufficient metal ions, this is dramatically different in the industrial system, where up to 30% of the film-forming species detected were ions. Additionally, the deposition rate in the industrial system was about one order of magnitude higher compared to the laboratory system.

引用次数: 0

Industrial reactive sputter deposition of TiZrN coatings: The role of nitrogen partial pressure

IF 5.3 2区材料科学 Q1 MATERIALS SCIENCE, COATINGS & FILMS

Surface & Coatings Technology

Pub Date : 2025-02-05 DOI: 10.1016/j.surfcoat.2025.131873

Sahand Behrangi , Diederik Depla , Pavel Souček , Zsolt Czigány , Vilma Buršíková , Katalin Balázsi , Petr Vašina

Reactive sputter deposition of TiN, ZrN, and TiZrN coatings at different nitrogen partial pressures was performed under industrial conditions using a combinatorial approach. For all coatings, the nitrogen content rose with increasing nitrogen partial pressure and then leveled off above a given pressure. The ZrN coatings exhibited a columnar structure irrespective of the nitrogen pressure used. In contrast, the microstructure of TiN and TiZrN varied depending on the nitrogen partial pressure. A different behavior of the crystallite size as a function of the nitrogen partial pressure was observed for TiN and ZrN. A strong dependence was noticed for TiN. This contrasted with the behavior of ZrN which had much smaller crystallites. Smaller crystallites were also observed in the TiZrN coatings and the influence of the nitrogen partial pressure and the Ti/(Ti + Zr) ratio on these coatings was weak. The coloration of the coatings was notably influenced by nitrogen partial pressure. The level of red for the TiN and TiZrN coatings and the yellow hue for the ZrN coatings significantly increased with nitrogen partial pressure. The hardness of all TiZrN coatings peaked at intermediate nitrogen partial pressures, which indicates that nitrogen partial pressure enables the optimization of mechanical properties. The highest measured hardness (31 GPa) was obtained at a Ti/(Ti + Zr) ratio of 0.50 although similar values were obtained irrespective of the metallic elements. This study demonstrates the potential to enhance the mechanical properties of TiN by incorporating Zr provided the correct nitrogen partial pressure is selected.

{"title":"Industrial reactive sputter deposition of TiZrN coatings: The role of nitrogen partial pressure","authors":"Sahand Behrangi , Diederik Depla , Pavel Souček , Zsolt Czigány , Vilma Buršíková , Katalin Balázsi , Petr Vašina","doi":"10.1016/j.surfcoat.2025.131873","DOIUrl":"10.1016/j.surfcoat.2025.131873","url":null,"abstract":"<div><div>Reactive sputter deposition of TiN, ZrN, and TiZrN coatings at different nitrogen partial pressures was performed under industrial conditions using a combinatorial approach. For all coatings, the nitrogen content rose with increasing nitrogen partial pressure and then leveled off above a given pressure. The ZrN coatings exhibited a columnar structure irrespective of the nitrogen pressure used. In contrast, the microstructure of TiN and TiZrN varied depending on the nitrogen partial pressure. A different behavior of the crystallite size as a function of the nitrogen partial pressure was observed for TiN and ZrN. A strong dependence was noticed for TiN. This contrasted with the behavior of ZrN which had much smaller crystallites. Smaller crystallites were also observed in the TiZrN coatings and the influence of the nitrogen partial pressure and the Ti/(Ti + Zr) ratio on these coatings was weak. The coloration of the coatings was notably influenced by nitrogen partial pressure. The level of red for the TiN and TiZrN coatings and the yellow hue for the ZrN coatings significantly increased with nitrogen partial pressure. The hardness of all TiZrN coatings peaked at intermediate nitrogen partial pressures, which indicates that nitrogen partial pressure enables the optimization of mechanical properties. The highest measured hardness (31 GPa) was obtained at a Ti/(Ti + Zr) ratio of 0.50 although similar values were obtained irrespective of the metallic elements. This study demonstrates the potential to enhance the mechanical properties of TiN by incorporating Zr provided the correct nitrogen partial pressure is selected.</div></div>","PeriodicalId":22009,"journal":{"name":"Surface & Coatings Technology","volume":"499 ","pages":"Article 131873"},"PeriodicalIF":5.3,"publicationDate":"2025-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143291590","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Influence of microstructural parameters on thermal cycling behavior of DVC-TBC systems

IF 5.3 2区材料科学 Q1 MATERIALS SCIENCE, COATINGS & FILMS

Surface & Coatings Technology

Pub Date : 2025-02-05 DOI: 10.1016/j.surfcoat.2025.131881

Giulia Pedrizzetti , Erica Scrinzi , Elvira Giubbolini , Rita Bottacchiari , Laura Paglia , Francesco Marra , Giovanni Pulci

This study presents a novel approach to characterizing crack distribution and bond coat roughness in Thermal Barrier Coatings (TBCs) with dense vertically cracked (DVC) top coats and MCrAlY bond coats, aiming to correlate microstructural features with durability and failure mechanisms. A MATLAB®-based image analysis routine was developed to extract microstructural and morphological features from BSE-SEM micrographs. A novel parameter, the equivalent through-the-thickness crack density (ρ*_ttc), was introduced to provide a more accurate representation of crack distribution compared to conventional crack density. Additionally, standard (Ra, Rsm) and advanced (Rdq, Rdr) surface descriptors were calculated directly from SEM micrographs. TBCs with CoNiCrAlY bond coats were deposited on single-crystal and polycrystalline nickel-based superalloys and thermal cycling resistance was investigated with furnace cycle tests (FCT) at 1150 °C and 1100 °C. FCT at 1150 °C revealed that higher ρ*_ttc correlated with improved thermal cycling resistance due to enhanced strain tolerance, while conventional crack density showed no clear link to durability. Similarly, bond coat roughness analysis demonstrated that higher surface tortuosity, quantified by Rdr, associates with extended TBC lifespan by improving mechanical interlocking and stress dissipation. Additionally, a new non-destructive technique for real-time damage assessment using automatic thermographic image analysis was introduced. FCT at 1100 °C confirmed that coatings with higher ρ*_ttc and Rdr exhibit superior resistance to delamination cracks propagation, whereas lower values result in less effective strain tolerance and stress dissipation mechanisms.

{"title":"Influence of microstructural parameters on thermal cycling behavior of DVC-TBC systems","authors":"Giulia Pedrizzetti , Erica Scrinzi , Elvira Giubbolini , Rita Bottacchiari , Laura Paglia , Francesco Marra , Giovanni Pulci","doi":"10.1016/j.surfcoat.2025.131881","DOIUrl":"10.1016/j.surfcoat.2025.131881","url":null,"abstract":"<div><div>This study presents a novel approach to characterizing crack distribution and bond coat roughness in Thermal Barrier Coatings (TBCs) with dense vertically cracked (DVC) top coats and MCrAlY bond coats, aiming to correlate microstructural features with durability and failure mechanisms. A MATLAB®-based image analysis routine was developed to extract microstructural and morphological features from BSE-SEM micrographs. A novel parameter, the equivalent through-the-thickness crack density (ρ*<sub>ttc</sub>), was introduced to provide a more accurate representation of crack distribution compared to conventional crack density. Additionally, standard (Ra, Rsm) and advanced (Rdq, Rdr) surface descriptors were calculated directly from SEM micrographs. TBCs with CoNiCrAlY bond coats were deposited on single-crystal and polycrystalline nickel-based superalloys and thermal cycling resistance was investigated with furnace cycle tests (FCT) at 1150 °C and 1100 °C. FCT at 1150 °C revealed that higher ρ*<sub>ttc</sub> correlated with improved thermal cycling resistance due to enhanced strain tolerance, while conventional crack density showed no clear link to durability. Similarly, bond coat roughness analysis demonstrated that higher surface tortuosity, quantified by Rdr, associates with extended TBC lifespan by improving mechanical interlocking and stress dissipation. Additionally, a new non-destructive technique for real-time damage assessment using automatic thermographic image analysis was introduced. FCT at 1100 °C confirmed that coatings with higher ρ*<sub>ttc</sub> and Rdr exhibit superior resistance to delamination cracks propagation, whereas lower values result in less effective strain tolerance and stress dissipation mechanisms.</div></div>","PeriodicalId":22009,"journal":{"name":"Surface & Coatings Technology","volume":"499 ","pages":"Article 131881"},"PeriodicalIF":5.3,"publicationDate":"2025-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143372058","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Low temperature dependence of resistivity in obliquely sputter-deposited gold thin films

IF 5.3 2区材料科学 Q1 MATERIALS SCIENCE, COATINGS & FILMS

Surface & Coatings Technology

Pub Date : 2025-02-05 DOI: 10.1016/j.surfcoat.2025.131884

Nicolas Martin , Eliot Martin , Jean-Marc Cote , Fabrice Sthal , Joseph Gavoille , Marina Raschetti , Stefania Oliveri

We report on the electrical resistivity at low temperature of Au thin films 400 nm thick deposited by DC magnetron sputtering using oblique angle deposition (OAD). The deposition angle α is gradually and systematically changed from 0° to 80°. A tilted and voided columnar structure is produced for deposition angles higher than 60°, whereas the lowest angles lead to a dense and compact structure with no clear cross-section morphology. Resistivity vs. temperature measurements reveal a typical metallic-like behavior in the range 7–300 K whatever the deposition angle. The latter gives rise to a significant increase of residual resistivity and temperature coefficient of resistance, and again for the most grazing angles, i.e., α > 60°. The Bloch-Grüneisen model is assumed for understanding the evolution of electron-phonon interactions as a function of the deposition angle. This enhanced resistivity is connected to the structural defects and the porous architecture especially emphasized for glancing angles, and the strengthening of the electron-phonon coupling for high deposition angles.

{"title":"Low temperature dependence of resistivity in obliquely sputter-deposited gold thin films","authors":"Nicolas Martin , Eliot Martin , Jean-Marc Cote , Fabrice Sthal , Joseph Gavoille , Marina Raschetti , Stefania Oliveri","doi":"10.1016/j.surfcoat.2025.131884","DOIUrl":"10.1016/j.surfcoat.2025.131884","url":null,"abstract":"<div><div>We report on the electrical resistivity at low temperature of Au thin films 400 nm thick deposited by DC magnetron sputtering using oblique angle deposition (OAD). The deposition angle <em>α</em> is gradually and systematically changed from 0° to 80°. A tilted and voided columnar structure is produced for deposition angles higher than 60°, whereas the lowest angles lead to a dense and compact structure with no clear cross-section morphology. Resistivity <em>vs.</em> temperature measurements reveal a typical metallic-like behavior in the range 7–300 K whatever the deposition angle. The latter gives rise to a significant increase of residual resistivity and temperature coefficient of resistance, and again for the most grazing angles, <em>i.e.</em>, α > 60°. The Bloch-Grüneisen model is assumed for understanding the evolution of electron-phonon interactions as a function of the deposition angle. This enhanced resistivity is connected to the structural defects and the porous architecture especially emphasized for glancing angles, and the strengthening of the electron-phonon coupling for high deposition angles.</div></div>","PeriodicalId":22009,"journal":{"name":"Surface & Coatings Technology","volume":"499 ","pages":"Article 131884"},"PeriodicalIF":5.3,"publicationDate":"2025-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143224794","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Achieving a crackless, abrasion- and corrosion-resistant oxide coating on Ti-Zr-Hf-Nb-Al-Y refractory high-entropy alloy through Y alloying and high-temperature fast oxidation

IF 5.3 2区材料科学 Q1 MATERIALS SCIENCE, COATINGS & FILMS

Surface & Coatings Technology

Pub Date : 2025-02-05 DOI: 10.1016/j.surfcoat.2025.131882

Nengbin Hua , Rui Wang , Zhongya Qian , Rongpei Shi , Da Zeng , Xiongwei Liang , Xinxiong Xiao , Hanxin Lin , Wenfei Lu , Jun Shen , Peter K. Liaw

High-temperature oxidation is a facile technique to fabricate a wear- and corrosion-resistant oxide coating for metals. However, TiZrHfNb-based refractory high-entropy alloys (RHEAs) are prone to suffer from surface cracking during high-temperature oxidation processes, which is a common outcome observed in the high-temperature oxidation behavior of titanium alloys. This study introduces a novel approach to mitigate high-temperature oxidation cracking in the TiZrHfNbAl_0.5 RHEA by leveraging the synergistic effects of Y-alloying and precise oxidation control. It's found that surface cracking observed in the TiZrHfNbAl_0.5 RHEA following oxidation at 1000 °C is primarily attributed to the formation of needle-like (ZrHf)O₂ within the oxide layer. By combining Y-doping and an oxidation treatment at 1000 °C for 8 min, the generation of (ZrHf)O₂ is effectively suppressed, while a dispersion Y-Al-rich oxides is promoted, thereby creating a pinning effect that results in the formation of a crack-free oxide coating. Consequently, the oxidized TiZrHfNbAl_0.5Y_0.1 RHEA exhibits a wear rate that is two orders of magnitude lower and a corrosion current density that is one order of magnitude lower than those of the Ti6Al4V (wt%) alloy. A systematic analysis is also carried out to elucidate the oxidation mechanism underpinning this exceptionally wear- and corrosion-resistant RHEA. The present work offers new possibilities for the industrial applications of RHEAs in abrasive and corrosive environments.

{"title":"Achieving a crackless, abrasion- and corrosion-resistant oxide coating on Ti-Zr-Hf-Nb-Al-Y refractory high-entropy alloy through Y alloying and high-temperature fast oxidation","authors":"Nengbin Hua , Rui Wang , Zhongya Qian , Rongpei Shi , Da Zeng , Xiongwei Liang , Xinxiong Xiao , Hanxin Lin , Wenfei Lu , Jun Shen , Peter K. Liaw","doi":"10.1016/j.surfcoat.2025.131882","DOIUrl":"10.1016/j.surfcoat.2025.131882","url":null,"abstract":"<div><div>High-temperature oxidation is a facile technique to fabricate a wear- and corrosion-resistant oxide coating for metals. However, TiZrHfNb-based refractory high-entropy alloys (RHEAs) are prone to suffer from surface cracking during high-temperature oxidation processes, which is a common outcome observed in the high-temperature oxidation behavior of titanium alloys. This study introduces a novel approach to mitigate high-temperature oxidation cracking in the TiZrHfNbAl<sub>0.5</sub> RHEA by leveraging the synergistic effects of Y-alloying and precise oxidation control. It's found that surface cracking observed in the TiZrHfNbAl<sub>0.5</sub> RHEA following oxidation at 1000 °C is primarily attributed to the formation of needle-like (ZrHf)O<sub>2</sub> within the oxide layer. By combining Y-doping and an oxidation treatment at 1000 °C for 8 min, the generation of (ZrHf)O<sub>2</sub> is effectively suppressed, while a dispersion Y-Al-rich oxides is promoted, thereby creating a pinning effect that results in the formation of a crack-free oxide coating. Consequently, the oxidized TiZrHfNbAl<sub>0.5</sub>Y<sub>0.1</sub> RHEA exhibits a wear rate that is two orders of magnitude lower and a corrosion current density that is one order of magnitude lower than those of the Ti6Al4V (wt%) alloy. A systematic analysis is also carried out to elucidate the oxidation mechanism underpinning this exceptionally wear- and corrosion-resistant RHEA. The present work offers new possibilities for the industrial applications of RHEAs in abrasive and corrosive environments.</div></div>","PeriodicalId":22009,"journal":{"name":"Surface & Coatings Technology","volume":"499 ","pages":"Article 131882"},"PeriodicalIF":5.3,"publicationDate":"2025-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143225060","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Investigation of hot corrosion behavior of plasma sprayed cermet composite coatings on titanium and special steel alloys

IF 5.3 2区材料科学 Q1 MATERIALS SCIENCE, COATINGS & FILMS

Surface & Coatings Technology

Pub Date : 2025-02-05 DOI: 10.1016/j.surfcoat.2025.131883

Madhu Sudana Reddy G , C. Durga Prasad , Pavan Kumar B K , Shrishail B. Sollapur , Vishwanatha S , S. Mohan Kumar , G.S. Pradeep Kumar , Mohd Hamid Hussain

In the present study, titanium-15 alloy and a special steel alloy (MDN 420) were used as base materials. These components are employed in high-temperature applications. Three types of pure powders were deposited on titanium-15 and a special steel (MDN 420) alloys. The three coatings were 35 % (WC-Co) + 65 % (Cr₃C₂-NiCr), 70 % NiCrAlY + 30 % TiO₂, and 70 % NiCrAlY+25%Cr₂O₃ + 5%YSZ. The coatings and base alloys underwent various metallurgical, mechanical, and hot corrosion tests. The hot corrosion behavior of the coatings was investigated in a Na₂SO₄–60%V₂O₅ molten salt medium at 700 °C, with an accuracy of ±5 °C. Each test cycle consisting of 50 cycles, with heating followed by 1 h cooling for 20 min. When three coatings were compared, NiCrAlY+Cr₂O₃ + YSZ coating exhibited superior resistance to hot corrosion on both the alloys. The enhanced corrosion resistance of the NiCrAlY+Cr₂O₃ + YSZ coating was attributed to the formation of a protective oxide layer containing Cr₂O₃.The tests were conducted in a highly acidic molten salt environment, with Na₂SO₄ being less soluble (60 % V₂O₅). The results showed that the NiCrAlY+Cr₂O₃ + YSZ coating displayed better corrosion resistance for titanium-15 and MDN 420 alloys, when compared to the other two coatings. The formation of an oxide layer containing Cr₂O₃ was the main reason for the improved corrosion resistance.

{"title":"Investigation of hot corrosion behavior of plasma sprayed cermet composite coatings on titanium and special steel alloys","authors":"Madhu Sudana Reddy G , C. Durga Prasad , Pavan Kumar B K , Shrishail B. Sollapur , Vishwanatha S , S. Mohan Kumar , G.S. Pradeep Kumar , Mohd Hamid Hussain","doi":"10.1016/j.surfcoat.2025.131883","DOIUrl":"10.1016/j.surfcoat.2025.131883","url":null,"abstract":"<div><div>In the present study, titanium-15 alloy and a special steel alloy (MDN 420) were used as base materials. These components are employed in high-temperature applications. Three types of pure powders were deposited on titanium-15 and a special steel (MDN 420) alloys. The three coatings were 35 % (WC-Co) + 65 % (Cr<sub>3</sub>C<sub>2</sub>-NiCr), 70 % NiCrAlY + 30 % TiO<sub>2</sub>, and 70 % NiCrAlY+25%Cr<sub>2</sub>O<sub>3</sub> + 5%YSZ. The coatings and base alloys underwent various metallurgical, mechanical, and hot corrosion tests. The hot corrosion behavior of the coatings was investigated in a Na<sub>2</sub>SO<sub>4</sub>–60%V<sub>2</sub>O<sub>5</sub> molten salt medium at 700 °C, with an accuracy of ±5 °C. Each test cycle consisting of 50 cycles, with heating followed by 1 h cooling for 20 min. When three coatings were compared, NiCrAlY+Cr<sub>2</sub>O<sub>3</sub> + YSZ coating exhibited superior resistance to hot corrosion on both the alloys. The enhanced corrosion resistance of the NiCrAlY+Cr<sub>2</sub>O<sub>3</sub> + YSZ coating was attributed to the formation of a protective oxide layer containing Cr<sub>2</sub>O<sub>3</sub>.The tests were conducted in a highly acidic molten salt environment, with Na<sub>2</sub>SO<sub>4</sub> being less soluble (60 % V<sub>2</sub>O<sub>5</sub>). The results showed that the NiCrAlY+Cr<sub>2</sub>O<sub>3</sub> + YSZ coating displayed better corrosion resistance for titanium-15 and MDN 420 alloys, when compared to the other two coatings. The formation of an oxide layer containing Cr<sub>2</sub>O<sub>3</sub> was the main reason for the improved corrosion resistance.</div></div>","PeriodicalId":22009,"journal":{"name":"Surface & Coatings Technology","volume":"499 ","pages":"Article 131883"},"PeriodicalIF":5.3,"publicationDate":"2025-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143377495","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0