Endre søk
Begrens søket
123 101 - 130 of 130
RefereraExporteraLink til resultatlisten
Permanent link
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annet format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annet språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf
Treff pr side
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sortering
  • Standard (Relevans)
  • Forfatter A-Ø
  • Forfatter Ø-A
  • Tittel A-Ø
  • Tittel Ø-A
  • Type publikasjon A-Ø
  • Type publikasjon Ø-A
  • Eldste først
  • Nyeste først
  • Skapad (Eldste først)
  • Skapad (Nyeste først)
  • Senast uppdaterad (Eldste først)
  • Senast uppdaterad (Nyeste først)
  • Disputationsdatum (tidligste først)
  • Disputationsdatum (siste først)
  • Standard (Relevans)
  • Forfatter A-Ø
  • Forfatter Ø-A
  • Tittel A-Ø
  • Tittel Ø-A
  • Type publikasjon A-Ø
  • Type publikasjon Ø-A
  • Eldste først
  • Nyeste først
  • Skapad (Eldste først)
  • Skapad (Nyeste først)
  • Senast uppdaterad (Eldste først)
  • Senast uppdaterad (Nyeste først)
  • Disputationsdatum (tidligste først)
  • Disputationsdatum (siste først)
Merk
Maxantalet träffar du kan exportera från sökgränssnittet är 250. Vid större uttag använd dig av utsökningar.
  • 101.
    Sadeghimeresht, Esmaeil
    et al.
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Markocsan, Nicolaie
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Electrochemical Behavior of Bilayer Thermal-Spray Coatings in Low-Temperature Corrosion Protection2017Inngår i: Coatings, ISSN 2079-6412, Vol. 7, nr 10, s. 1-13, artikkel-id 162Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Cr3C2-NiCr coatings are greatly used to protect critical components in corrosive environments and to extend their lifetime and/or improve functional performance. However, the pores formed during spraying restrict the coating’s applicability area for many corrosion protection applications. To overcome this technical challenge, bilayer coatings have been developed, in which an additional layer (the so-called intermediate layer) is deposited on the substrate before spraying the Cr3C2-NiCr coating (the so-called top layer). The corrosion behavior of the bilayer coating depends on the composition and microstructure of each layer. In the present work, different single-layer coatings (i.e., Cr3C2-NiCr, Fe- and Ni-based coatings) were initially sprayed by a high-velocity air fuel (HVAF) process. Microstructure analysis, as well as electrochemical tests, for example, open-circuit potential (OCP) and polarization tests, were performed. The potential difference (Delta E) had a great influence on galvanic corrosion between the top and intermediate layers, and thus, the coatings were ranked based on the OCP values (from high to low) as follows: NiCoCrAlY > NiCr > Cr3C2-NiCr > NiAl > Fe-based coatings (alloyed with Cr) > pure Ni. The Ni-based coatings were chosen to be further used as intermediate layers with the Cr3C2-NiCr top layer due to their capabilities to show high OCP. The corrosion resistance (R-p) of the bilayer coatings was ranked (from high to low) as follows: NiCoCrAlY/Cr3C2-NiCr > NiCr/Cr3C2-NiCr > NiAl/Cr3C2-NiCr > Ni/Cr3C2-NiCr. It was shown that splat boundaries and interconnected pores are detrimental for corrosion resistance, however, a sufficient reservoir of protective scale-forming elements (such as Cr or/and Al) in the intermediate layer can significantly improve the corrosion resistance.

  • 102.
    Sadeghimeresht, Esmaeil
    et al.
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Markocsan, Nicolaie
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Huhtakangas, M.b
    M. H. Engineering AB, 691 42 Karlskoga, Sweden.
    Joshi, Shrikant V.
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Forskningsmiljön produktionsteknik(PTW).
    Isothermal oxidation of HVAF-sprayed Ni-based chromia, alumina and mixed-oxide scale forming coatings in ambient air2017Inngår i: Surface & Coatings Technology, ISSN 0257-8972, E-ISSN 1879-3347, Vol. 316, s. 10-21Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The power generation industry has been progressively shifting towards higher operating steam temperatures and pressures to increase efficiency and reduce CO2 emissions. However, higher operating temperatures lead to more aggressive oxidation of the boiler components. A promising route to improve the durability of degradation-prone components is through deployment of high-performance coatings. In the present work, four Ni-based coatings - Ni21Cr, Ni5Al, Ni21Cr9Mo, and Ni21Cr7Al1Y - thermally sprayed by the high-velocity air fuel (HVAF) technique on boiler steel (16Mo3) substrates were investigated. The isothermal oxidation behavior of the coatings was studied in ambient air environment at 600 °C for different time intervals i.e. 1, 5, 10, 24, 48, 96, and 168 h. The oxidation behavior of the as-sprayed and polished coatings was compared. The protective α-Al2O3 was not detected on the exposed alumina-forming NiAl coating. On the other hand, Cr2O3 along with a small amount of NiO were the main oxidation products on the surface of the NiCr and NiCrMo coatings, and were found to be relatively less protective. The mixed-oxide scale forming NiCrAlY coatings showed the best oxidation resistance due to the formation of a thin and slow-growing Al2O3 scale along with Ni(Al,Cr)2O4 and Cr2O3. The polished coatings were found to significantly reduce the oxidation rate in each case as the protective scale-forming elements were more uniformly supplied to the surface oxide scale by removing the surface asperities. © 2017 Elsevier B.V.

  • 103.
    Sadeghimeresht, Esmaeil
    et al.
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Markocsan, Nicolaie
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Hussain, Tanvir
    Univ Nottingham, Fac Engn, Nottingham NG7 2RD, England.
    Huhtakangas, Matti
    MH Engn AB, S-69142 Karlskoga, Sweden.
    Joshi, Shrikant V.
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Effect of SiO2 Dispersion on Chlorine-Induced High-Temperature Corrosion of High-Velocity Air-Fuel Sprayed NiCrMo Coating2018Inngår i: Corrosion, ISSN 0010-9312, E-ISSN 1938-159X, Vol. 74, nr 9, s. 984-1000Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    NiCrMo coatings with and without dispersed SiO2 were deposited using high-velocity air-fuel technique. Thermogravimetric experiments were conducted in 5% O-2 + 500 vppm HCl + N-2 with and without a KCl deposit at 600 degrees C for up to 168 h. The SiO2-containing coating showed lower weight change as a result of formation of a protective and adherent Cr-rich oxide scale. SiO2 decelerated short-circuit diffusion of Cr3+ through scale's defects, e.g., vacancies, and promoted the selective oxidation of Cr to form the protective Cr-rich oxide scale. Furthermore, the presence of SiO2 led to less subsurface depletion of Cr in the coating, and accordingly less corrosion of the substrate. The formed corrosion product on the SiO2-free coating was highly porous, non-adherent, and thick.

  • 104.
    Sadeghimeresht, Esmaeil
    et al.
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Markocsan, Nicolaie
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avd för industriell produktion. Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Joshi, Shrikant V.
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Forskningsmiljön produktionsteknik(PTW). Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Isothermal oxidation behavior of HVAF-sprayed Ni and NiCr coatings in H2-H2O environment2017Inngår i: Surface & Coatings Technology, ISSN 0257-8972, E-ISSN 1879-3347, Vol. 317, s. 17-25Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The formation of a protective chromia scale on stainless steels is known to be suppressed by the presence of water vapor in reducing conditions. Thermal spray coatings present a promising approach to improve the durability of steels by transferring the first line of oxidation attack from the bulk steel to the coating. In the present work, isothermal oxidation behavior of Ni and NiCr coatings deposited by High-Velocity Air Fuel (HVAF) process on 304L stainless steel was investigated at 600 degrees C for 168 h. Ar-10%H-2-20%H2O was selected as the oxidation environment to study the oxidation behavior of the coatings in a low pO(2) environment containing H2 and H2O. BIB/ SEM, EDS, and XRD techniques were used to characterize the as-sprayed coatings and to investigate the oxidation mechanisms in the coated samples. Results showed that both Ni and NiCr coatings imparted oxidation protection to the 304L substrate. The chromia-forming 304L steel presented a duplex but non-protective oxide scale comprising of an outer Fe3O4 layer on an inner (Fe, Cr)(3)O-4-spinel oxide. In contrast, the NiCr coating presented superior oxidation behavior due to the formation of a continuous, thin, and slow-growing Cr2O3 scale. The Ni coating, too, protected the substrate owing to limited nucleation and growth of the deleterious NiO scale in the low-oxygen -activity environment. (C) 2017 Elsevier B.V. All rights reserved.

  • 105.
    Sadeghimeresht, Esmaeil
    et al.
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Markocsan, Nicolaie
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Nylen, Per
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Corrosion behavior of HVAF-sprayed Bi-layer coatings: Effect of intermediate layer's microstructure and chemical composition2017Inngår i: Proceedings of the International Thermal Spray Conference & Exposition (ITSC 201), New York: Curran Associates, Inc , 2017, Vol. 2, s. 941-945Konferansepaper (Fagfellevurdert)
  • 106.
    Sadeghimeresht, Esmaeil
    et al.
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Markocsan, Nicolaie
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Nylen, Per
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Microstructural characteristics and corrosion behavior of HVAF- and HVOF-sprayed Fe-based coatings2017Inngår i: Surface & Coatings Technology, ISSN 0257-8972, E-ISSN 1879-3347, Vol. 318, s. 365-373Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Fe-based coatings have been shown to be viable alternatives to the more expensive and less environmentally friendly Co- and Ni-based coatings. In the present work, the microstructural characteristics and corrosion behavior of Fe-based coatings deposited by high-velocity air fuel (HVAF) and high-velocity oxy fuel (HVOF) processes were comparatively investigated. Different sets of powder composition and particle size were used to decrease the porosity and increase the corrosion resistance of the coatings. The corrosion behavior of the coatings was studied using electrochemical techniques, including open-circuit potential (OCP) and polarization tests in 3.5 wt% NaCl at 25 °C. Techniques such as scanning electron microscopy (SEM), energy dispersive spectrometry (EDS), and X-ray diffractometry (XRD) were used to characterize the as-sprayed and corroded coatings. The results revealed that the HVAF coatings had lower porosity and oxide content than the HVOF coatings. The polarization tests confirmed that the HVAF coatings sprayed with finer particle size (− 36 + 20 μm) have higher polarization resistance (Rp) than the coatings produced by powders (− 53 + 20 μm). Based on SEM analysis, it was observed that corrosion initiated and grew through the surface defects of the coating and propagated through inter-lamellar boundaries.

    Keywords

  • 107.
    Sadeghimeresht, Esmaeil
    et al.
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT). Amirkabir University of Tehran, Tarbiat Modares University of Tehran.
    Markocsan, Nicolaie
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Nylén, Per
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Forskningsmiljön produktionsteknik(PTW).
    A Comparative Study of Corrosion Resistance for HVAF-Sprayed Fe- and Co-Based Coatings2016Inngår i: Coatings, ISSN 2079-6412, Vol. 6, nr 2, s. 1-15Artikkel, forskningsoversikt (Fagfellevurdert)
    Abstract [en]

    There is an increasing demand to replace Co-based coatings with cheap and environmentally friendly Fe-based coatings in corrosive environments. The main objective of this work was to evaluate whether Fe-based coatings could present a better corrosion performance than Co-based coatings. Therefore, two types of Fe-based and one type of Co-based coatings with chemical compositions (in wt %) of Fe-28Cr-16Ni-1.85C (FeNiCrC), Fe-17Cr-12Ni (FeNiCr), andCo-28Cr-1C (CoCrC) were produced by High Velocity Air Fuel (HVAF) spraying. The corrosion behavior of the coatings was studied comparatively by electrochemical tests in 3.5 wt % NaCl solutionat 25 C. The polarization test results showed that the FeCrNiC coating protected the underlying substrate better than the CoCrC coating, while the FeCrNi coating failed to hinder the penetration of corrosive ions. Electrochemical impedance spectroscopy (EIS) measurements revealed that thesolution penetrated into the coating through defects, however the corrosion process slowed down due to clogging of the interconnected defects by corrosion products. Increasing the in-flight average particle temperature from 1400 C to 1500 C led to a denser coating with fewer defects which seemed to improve the corrosion resistance of the FeCrNiC coating. The high-alloyed Fe-based coatings had the best corrosion protection performance and can thus be recommended as a potential alternative toCo-based coatings.

  • 108.
    Sadeghimeresht, Esmaeil
    et al.
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Markocsan, Nicolaie
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Nylén, Per
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    A comparative study on Ni-based coatings prepared by HVAF, HVOF, and APS methods for corrosion protection applications2016Inngår i: Journal of thermal spray technology (Print), ISSN 1059-9630, E-ISSN 1544-1016, Vol. 25, nr 8, s. 1604-1616Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Selection of the thermal spray process is the most important step towards a proper coating solution for a given application as important coating characteristics such as adhesion, and microstructure, etc. are highly dependent on it. In the present work, a process-microstructure-properties-performance correlation study was performed in order to figure out the main characteristics and corrosion performance of the coatings produced by different thermal spray techniques such as high-velocity airfuel (HVAF), high-velocity oxy fuel (HVOF), and atmospheric plasma spraying (APS). Previously optimized HVOF and APS process parameters were used to deposit Ni, NiCr, and NiAl coatings and compare with HVAF-sprayed coatings with randomly selected process parameters. As the HVAF process presented the best coating characteristics and corrosion behavior, various process parameters,e.g., feed rate and stand off distance (SoD) were investigated to systematically optimize the HVAF coatings in terms of high density and corrosion properties. The coatings with lower porosity and better corrosion behavior were obtained at an average SoD of 300 mm for the Ni and NiAl coatings and a SoDof 250 mm for the NiCr coating. Increasing the feed rate to 150 g/min in the Ni and NiAl coatings decreased the coating pores and accordingly increased the Rp.

  • 109.
    Sadeghimeresht, Esmaeil
    et al.
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Markocsan, Nicolaie
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Nylén, Per
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Duplex thermal spray coatings: a critical approach to extend the service-life of metallic components2016Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    Corrosion is a common problem for many metallic components used today in a wide range of industries. Thermal spraying is a promising approach to properly protect the metallic structure from the deleterious effects of the environment that surrounds it. In this study, three types of coating systems (A: single layer of Cr3C2-NiCr, B: Ni/Cr3C2-NiCr and C: NiCr/Cr3C2-NiCr) were deposited using HVAF process. Electrochemical tests were employed to investigate the corrosion susceptibility of the above systems. OCP, polarization and EIS tests were performed in 3.5 wt.% NaCl solution at 25°C. Results showed that bi-layer coatings exhibited a better corrosion resistance than the single-layer coating. While coating system A demonstrated some signs of pitting due to the penetration of tiny chloride ions through the defects of the coating, which eventually led to the destruction of the substrate close to the interface, coating systems B and C showed much better anti-corrosion behavior. Moreover, the results confirmed that gradual changes of the composition from the top coating to substrate reduced the possibility of galvanic corrosion. SEM, EDAX, and XRD were used to characterize the corrosion products along the surface and the cross-section of specimens.

  • 110.
    Sadeghimeresht, Esmaeil
    et al.
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avd för tillverkningsprocesser.
    Markocsan, Nicolaie
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avd för tillverkningsprocesser.
    Nylén, Per
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avd för industriell produktion.
    HVAF thermal spray Fe-based coating: An environmentally acceptable alternative to cobalt-based coating2015Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Fe-based coatings were widely used in the corrosive environment of various indus-tries. It was replacing expensive cobalt-based alloys, which face a ban in the future due to serious health and environmental risks. The aim of the present work was to compare low temperature corrosion behavior of some Fe- and Co-based coatings produced by High-Velocity Air Fuel (HVAF) thermal spraying. Polarization and elec-trochemical impedance spectroscopy (EIS) tests were carried out in 3.5 wt.% NaCl solution at 25°C. The microstructures were analyzed using optical microscopy (OM) and scanning electron microscopy (SEM) to characterize the morphologies of both Fe- and Co-based coatings and analyze the exposed products along the surface and cross-section of specimens. The results revealed that the high-chromium Fe-based coating protected the underlying substrate better than Co-based coating.

  • 111.
    Sadeghimeresht, Esmaeil
    et al.
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Markocsan, Nicolaie
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Nylén, Per
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Microstructural and electrochemical characterization of Ni-based bi-layer coatings produced by the HVAF process2016Inngår i: Surface & Coatings Technology, ISSN 0257-8972, E-ISSN 1879-3347, Vol. 304, s. 606-619Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Bi-layer coating systems comprising a Cr3C2-NiCr coating with different underlying coatings of Ni, NiCr, NiCoCrAlY, and CoNiCrAlY were deposited on 304L stainless steel substrates using the high-velocity air fuel (HVAF) process. The corrosion behavior of the coating systems was studied using electrochemical and immersion tests in 3.5 wt% NaCl at 25 °C. The higher open-circuit potential (OCP) value of the NiCoCrAlY coating (− 120 mV/SCE) compared to the value of the Cr3C2-NiCr coating (− 230 mV/SCE) revealed that the underlying NiCoCrAlY coating was sacrificially protected by Cr3C2-NiCr coating. The polarization resistance (Rp) of the bi-layer coatings with the different underlying coatings of Ni, NiCr, NiCoCrAlY and CoNiCrAlY was approximately 77, 189, 487, and 74 kΩ·cm2 respectively, while the value was 101 kΩ·cm2 for the single-layer Cr3C2-NiCr coating and 30 kΩ·cm2 for the 304L substrate, which confirmed a higher corrosion protection of the NiCoCrAlY coating. The electrochemical impedance spectroscopy (EIS) results showed that the corrosion resistance of the 304L substrate was significantly improved by adding an intermediate layer of NiCoCrAlY to the Cr3C2-NiCr coating. Results of the immersion tests confirmed that the underlying coatings in the different bi-layer coating systems acted as protective barriers. Moreover, the NiCoCrAlY coating showed the best corrosion protection among the investigated underlying coatings.

  • 112.
    Sadeghimeresht, Esmaeil
    et al.
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Markocsan, Nicolaie
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Nylén, Per
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Microstructure effect of intermediate coat layer on corrosion behavior of HVAF-sprayed bi-layer coatings2017Inngår i: Journal of thermal spray technology (Print), ISSN 1059-9630, E-ISSN 1544-1016, Vol. 26, nr 1-2, s. 243-253Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The inherent pores and carbides of Cr3C2-NiCr coatings significantly reduce the corrosion resistance, the former by providing preferential paths for ion diffusion and the latter by forming cathodic sites in galvanic couples (between NiCr and Cr3C2). Adding a dense intermediate layer (intermediate coat layer) between the Cr3C2-NiCr coating (top coat) and substrate increases the corrosion protection of the coating if the layer acts as cathode in connection to the top coat. In the present work, NiCr, NiAl, and NiCoCrAlY layers were deposited by high-velocity air fuel(HVAF) process as intermediate coat layers for the Cr3C2-NiCr top coat. Effects of coating microstructure on corrosion behavior of single- and bi-layer coatings were studied by open circuitpotential (OCP) and polarization tests in 3.5 wt% NaCl at room temperature. A zero resistanceammeter (ZRA) technique was used to study the galvanic corrosion of the coupledtop and intermediate coat layers. Methods such as SEM and XRD were employed to characterize the as-sprayed and corroded coatings and investigate the corrosion mechanisms.The results showed that the NiCoCrAlY coating not only presented a more positive corrosion potential (Ecorr) than the Cr3C2-NiCr coating, but also provided a better passive layer than the single-phase NiCr and NiAl coatings.

  • 113.
    Sadeghimeresht, Esmaeil
    et al.
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Markocsan, Nicolaie
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Nylén, Per
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Björklund, Stefan
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Bi-layer thermal spray coatings: A critical approach to extend the service-life of metallic components2016Konferansepaper (Annet vitenskapelig)
  • 114.
    Sadeghimeresht, Esmaeil
    et al.
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avd Forskningsmiljön industriprocesser. Amirkabir University of Tehran, Tarbiat Modares University of Tehran.
    Markocsan, Nicolaie
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avd för tillverkningsprocesser.
    Nylén, Per
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Forskningsmiljön produktionsteknik(PTW).
    Björklund, Stefan
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avd för maskinteknik.
    Corrosion performance of bi-layer Ni/Cr2C3–NiCr HVAF thermal spray coating2016Inngår i: Applied Surface Science, ISSN 0169-4332, E-ISSN 1873-5584, Vol. 369, s. 470-481Artikkel, forskningsoversikt (Fagfellevurdert)
    Abstract [en]

    The corrosion behavior of three HVAF thermal spray coating systems (A: single-layer Ni, B: single-layer Cr2C3–NiCr coatings, and C: bi-layer Ni/Cr2C3–NiCr coating) was comparatively studied using immersion,salt spray, and electrochemical tests. Polarization and EIS results showed that the corrosion behavior of Cr2C3–NiCr coatings in 3.5 wt.% NaCl solution was significantly improved by adding the intermediate layer of Ni. It was illustrated that the polarization resistance of the bi-layer Ni/Cr2C3–NiCr and singlelayerCr2C3–NiCr coatings were around 194 and 38 k cm2, respectively. Microstructure analysis revealed that the bond coating successfully prevented the corrosion propagation toward the coating.

  • 115.
    Sadeghimeresht, Esmaeil
    et al.
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avd för tillverkningsprocesser.
    Markocsan, Nicolaie
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avd för tillverkningsprocesser.
    Nylén, Per
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avd för industriell produktion.
    Dizdar, S.
    Höganäs AB, Höganäs.
    Corrosion behavior of high-chromium Fe-based coatings produced by HVAF thermal spraying technique2015Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Fe-based coatings with different Cr content were prepared by high-velocity air fuel (HVAF) spraying on the surface of both carbon steel and stainless steel 304L. The corrosion behavior of the coatings were evaluated using polarization and electrochemical impedance spectroscopy (EIS) techniques in 3.5 wt.% NaCl solution. Microstructure of the coatings were evaluated by X-ray diffraction (XRD), optical microscopy (OM), scanning election microscopy (SEM), and Energy-dispersive X-ray spectroscopy (EDS) before and after corrosion testing. The experimental results indicated that Cr strongly increased the corrosion resistance of the coating. Furthermore, having an elemental composition closer to that of the substrate, the coatings showed lower susceptibility to galvanic corrosion, accordingly lower corrosion rate.

  • 116.
    Sadeghimeresht, Esmaeil
    et al.
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Raman, Sudharshan
    Nanyang Technological University, Singapore.
    Markocsan, Nicolaie
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Joshi, Shrikant V.
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Forskningsmiljön produktionsteknik(PTW).
    High Temperature Erosion-Corrosion behavior of HVAF- & HVOF-Sprayed Fe-based Coatings2017Konferansepaper (Annet vitenskapelig)
  • 117.
    Sadeghimeresht, Esmaeil
    et al.
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Reddy, Liam
    The University of Nottingham, Faculty of Engineering, Nottingham, United Kingdom.
    Hussain, Tanvir
    The University of Nottingham, Faculty of Engineering, Nottingham, United Kingdom.
    Huhtakangas, Matti
    M. H. Engineering AB, Karlskoga, Sweden.
    Markocsan, Nicolaie
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Joshi, Shrikant V.
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Forskningsmiljön produktionsteknik(PTW).
    Influence of KCl and HCl on high temperature corrosion of HVAF-sprayed NiCrAlY and NiCrMo coatings2018Inngår i: Materials & design, ISSN 0264-1275, E-ISSN 1873-4197, Vol. 148, s. 17-29Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The oxidation performance of NiCrAlY and NiCrMo coatings thermally sprayed by high velocity air-fuel (HVAF) technique has been investigated in a chloridizing-oxidizing environment, with and without a KCl deposit, at 600 °C for up to 168 h. Both coatings protected the substrate in the absence of KCl due to formation of a dense Cr-rich oxide scale. In the presence of KCl, Cl−/Cl2 diffused through a non-protective and porous NiCr2O4 scale formed on NiCrAlY, leading to formation of volatile CrCl3. On the other hand, Mo in NiCrMo stimulated the formation of a more protective Cr-rich oxide scale which increased the corrosion resistance by reducing Cl−/Cl2 diffusion.

  • 118.
    Sadeghimeresht, Esmaeil
    et al.
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Reddy, Liam
    The University of Nottingham, Faculty of Engineering, Nottingham, UK.
    Hussein, Tanvir
    The University of Nottingham, Faculty of Engineering, Nottingham, UK.
    Markocsan, Nicolaie
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Joshi, Shrikant V.
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Chlorine-induced high temperature corrosion of HVAF-sprayed Ni-based alumina and chromia forming coatings2018Inngår i: Corrosion Science, ISSN 0010-938X, E-ISSN 1879-0496, Vol. 132, nr March, s. 170-184Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Chlorine-induced corrosion of HVAF-sprayed Ni21Cr and Ni5Al coatings was investigated in 5 vol.% O2 + 500vppm HCl + N2 with and without KCl at 600 °C up to 168 h. Both coatings were protective in the absence of KCl. With KCl, Ni21Cr degraded through a two-stage mechanism: 1) formation of K2CrO4 followed by diffusion of Cl− through the oxide grain boundaries to yield chlorine and a non-protective oxide, and 2) inward diffusion of chlorine though defects in the non-protective oxide, leading to breakaway oxidation. Cl−/Cl2 could not diffuse through the protective alumina scale formed on Ni5Al, hence the corrosion resistance increased.

  • 119.
    Uczak de Goes, Wellington
    et al.
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Somhorst, Joop
    Volvo Car Corporation, Göteborg, Sweden.
    Markocsan, Nicolaie
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Gupta, Mohit Kumar
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Illkova, Kseniya
    Institute of Plasma Physics, Prague, Czech Republic.
    Suspension Plasma-Sprayed Thermal Barrier Coatings for Light-Duty Diesel Engines2019Inngår i: Journal of thermal spray technology (Print), ISSN 1059-9630, E-ISSN 1544-1016, Vol. 28, nr 7, s. 1674-1687Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Demands for improved fuel efficiency and reduced CO2 emissions of diesel engines have been the driving force for car industry in the past decades. One way to achieve this would be by using thermal spraying to apply a thermal insulation layer on parts of the engine’s combustion chamber. A candidate thermal spray process to give coatings with appropriate properties is suspension plasma spray (SPS). SPS, which uses a liquid feedstock for the deposition of finely structured columnar ceramic coatings, was investigated in this work for application in light-duty diesel engines. In this work, different spray processes and materials were explored to achieve coatings with optimized microstructure on the head of aluminum pistons used in diesel engine cars. The functional properties of the coatings were evaluated in single-cylinder engine experiments. The influence of thermo-physical properties of the coatings on their functional properties has been discussed. The influence of different spray processes on coating formation on the complex piston head profiles has been also discussed. The results show that SPS can be a promising technique for producing coatings on parts of the combustion chamber, which can possibly lead to higher engine efficiency in light-duty diesel engines.

  • 120.
    Vardelle, Armelle
    et al.
    University of Limoges, Limoges, France..
    Moreau, Christian
    Concordia University, Montreal, Canada..
    Akedo, Jun
    National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Japan..
    Ashrafizadeh, Hossein
    University of Alberta, Edmonton, Canada..
    Berndt, Christopher C.
    Swinburne University of Technology, Hawthorn, Australia..
    Berghaus, Jörg Oberste
    Swinburne University of Technology, Hawthorn, Australia..
    Boulos, Maher
    University of Sherbrooke, Sherbrooke, Canada..
    Brogan, Jeffrey
    Mesoscribe Technologies, Inc., St. James, USA..
    Bourtsalas, Athanasios C.
    Columbia University, New York, USA..
    Dolatabadi, Ali
    Concordia University, Montreal, Canada..
    Dorfman, Mitchell
    Oerlikon Metco, Inc., Westbury, USA.
    Eden, Timothy J.
    The Pennsylvania State University, State College, USA..
    Fauchais, Pierre
    University of Limoges, Limoges, France..
    Fisher, Gary
    Alberta Innovates - Technology Futures, Edmonton, Canada..
    Gaertner, Frank
    Helmut Schmidt University, Hamburg, Germany..
    Gindrat, Malko
    Oerlikon Metco AG,Wohlen, Switzerland..
    Henne, Rudolf
    German Aerospace Center (DLR), Stuttgart, Germany..
    Hyland, Margaret
    University of Auckland, Auckland, New Zealand..
    Irissou, Eric
    National Research Council of Canada, Boucherville, Canada..
    Jodoin, Bertrand
    University of Ottawa, Department of Mechanical Engineering, Ottawa, Canada.
    Jordan, Eric H.
    University of Connecticut, Storrs, USA..
    Khor, Khiam Aik
    Nanyang Technological University, Singapore, Singapore..
    Killinger, Andreas
    Universität Stuttgart, Stuttgart, Germany..
    Lau, Yuk-Chiu
    GE Power, Niskayuna, USA..
    Li, Chang-Jiu
    Xi’an Jiaotong University, Xi’an, China..
    Li, Li
    Praxair Surface Technologies, Inc.,Indianapolis, USA..
    Longtin, Jon
    Stony Brook University, Stony Brook, USA..
    Markocsan, Nicolaie
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Masset, Patrick J.
    Fraunhofer UMSICHT, Sulzbach-Rosenberg, Germany..
    Matejicek, Jiri
    Institute of Plasma Physics, Prague, Czech Republic..
    Mauer, Georg
    Forschungszentrum Jülich Institute of Energy and Climate Research, Jülich, Germany.
    McDonald, André
    University of Alberta, Edmonton, Canada..
    Mostaghimi, Javad
    University of Toronto,Toronto, Canada..
    Sampath, Sanjay
    Stony Brook University, Stony Brook, USA..
    Schiller, Günter
    German Aerospace Center (DLR), Stuttgart, Germany..
    Shinoda, Kentaro
    National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Japan..
    Smith, Mark F.
    Sandia National Laboratories, Albuquerque, USA..
    Syed, Asif Ansar
    German Aerospace Center (DLR), Stuttgart, Germany..
    Themelis, Nickolas J.
    Columbia University, New York, USA..
    Toma, Filofteia-Laura
    Fraunhofer Institute for Material and Beam Technology IWS, Dresden, Germany..
    Trelles, Juan Pablo
    University of Massachusetts Lowell, Lowell, USA..
    Vassen, Robert
    Forschungszentrum Jülich Institute of Energy and Climate Research, Jülich, Germany..
    Vuoristo, Petri
    Tampere University of Technology,Tampere, Finland..
    Erratum to The 2016 Thermal Spray Roadmap2017Inngår i: Journal of thermal spray technology (Print), ISSN 1059-9630, E-ISSN 1544-1016, Vol. 26, nr 5, s. 985-986Artikkel i tidsskrift (Fagfellevurdert)
  • 121.
    Vardelle, Armelle
    et al.
    University of Limoges, Limoges, France.
    Moreau, Christian
    Concordia University, Montreal, Canada.
    Akedo, Jun
    National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Japan.
    Ashrafizadeh, Hossein
    University of Alberta, Edmonton, Canada.
    Berndt, Christopher C.
    Swinburne University of Technology, Hawthorn, Australia.
    Berghaus, Jörg Oberste
    Swinburne University of Technology,Hawthorn, Australia.
    Boulos, Maher
    University of Sherbrooke, Sherbrooke, Canada.
    Brogan, Jeffrey
    Mesoscribe Technologies, Inc., St. James, USA.
    Bourtsalas, Athanasios C.
    Columbia University, New York, USA.
    Dolatabadi, Ali
    Concordia University, Montreal, Canada.
    Dorfman, Mitchell
    Oerlikon Metco, Inc., Westbury, USA.
    Eden, Timothy J.
    The Pennsylvania State University, State College, USA.
    Fauchais, Pierre
    University of Limoges, Limoges, France.
    Fisher, Gary
    Alberta Innovates - Technology Futures, Edmonton, Canada.
    Gaertner, Frank
    Helmut Schmidt University, Hamburg, Germany.
    Gindrat, Malko
    Oerlikon Metco AG,Wohlen, Switzerland.
    Henne, Rudolf
    German Aerospace Center (DLR), Stuttgart, Germany.
    Hyland, Margret
    University of Auckland, Auckland, New Zealand.
    Irissou, Eric
    National Research Council of Canada, Boucherville, Canada.
    Jodain, Bertrand
    University of Ottawa, Department of Mechanical Engineering, Ottawa, Canada.
    Jordan, Eric H.
    University of Connecticut, Storrs, USA.
    Khor, Khiam Aik
    Nanyang Technological University, Singapore, Singapore.
    Killinger, Andreas
    Universität Stuttgart, Stuttgart, Germany.
    Lau, Yuk-Chiu
    GE Power, Niskayuna, USA.
    Li, Chang-Jiu
    Xi’an Jiaotong University, Xi’an, China.
    Li, Li
    Praxair Surface Technologies, Inc.,Indianapolis, USA.
    Longtin, Jon
    Stony Brook University, Stony Brook, USA.
    Markocsan, Nicolaie
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Masset, Patrick J.
    Fraunhofer UMSICHT, Sulzbach-Rosenberg, Germany.
    Matejicek, Jiri
    Institute of Plasma Physics, Prague, Czech Republic.
    Mauer, Georg
    Forschungszentrum Jülich Institute of Energy and Climate Research, Jülich, Germany.
    McDonald, André
    University of Alberta, Edmonton, Canada.
    Mostaghimi, Javad
    University of Toronto,Toronto, Canada.
    Sampath, Sanjay
    Stony Brook University, Stony Brook, USA.
    Schiller, Günter
    German Aerospace Center (DLR), Stuttgart, Germany.
    Shinoda, Kentaro
    National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Japan.
    Smith, Mark F.
    Sandia National Laboratories, Albuquerque, USA.
    Syed, Asif Ansar
    German Aerospace Center (DLR), Stuttgart, Germany.
    Themelis, Nickolas J.
    Columbia University, New York, USA.
    Toma, Filofteia-Laura
    Fraunhofer Institute for Material and Beam Technology IWS, Dresden, Germany.
    Trelles, Juan Pablo
    University of Massachusetts Lowell, Lowell, USA.
    Vassen, Robert
    Forschungszentrum Jülich Institute of Energy and Climate Research, Jülich, Germany.
    Vuoristo, Petri
    Tampere University of Technology,Tampere, Finland.
    The 2016 Thermal Spray Roadmap2016Inngår i: Journal of thermal spray technology (Print), ISSN 1059-9630, E-ISSN 1544-1016, Vol. 25, nr 8, s. 1376-1440Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Considerable progress has been made over the last decades in thermal spray technologies, practices and applications. However, like other technologies, they have to continuously evolve to meet new problems and market requirements. This article aims to identify the current challenges limiting the evolution of these technologies and to propose research directions and priorities to meet these challenges. It was prepared on the basis of a collection of short articles written by experts in thermal spray who were asked to present a snapshot of the current state of their specific field, give their views on current challenges faced by the field and provide some guidance as to the R&D required to meet these challenges. The article is divided in three sections that deal with the emerging thermal spray processes, coating properties and function, and biomedical, electronic, aerospace and energy generation applications. © 2016, ASM International.

  • 122. Vassen, Robert
    et al.
    Cernuschi, Federico
    Rizzi, Gabriele
    Markocsan, Nicolaie
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avd för industriell produktion.
    Östergren, Lars
    Kloosterman, Arien
    Mevrel, Remy
    Feist, Jorg
    Nicholls, John
    Overview in the field of thermal barrier coatings including burner rig testing in the European Union2008Inngår i: Ceramics Japan, ISSN 0009-031X, Vol. 43, nr 5, s. 371-382Artikkel i tidsskrift (Annet vitenskapelig)
  • 123.
    Vassen, Robert
    et al.
    IEF-1, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany.
    Cernuschi, Federico
    CESI RICERCA, Power Generation Systems Dep. Milano, Italy.
    Rizzi, Gabriele
    Turbocoating.
    Scrivani, Andrea
    Turbocoating.
    Markocsan, Nicolaie
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avd för industriell produktion.
    Östergren, Lars
    Surface Technology, Volvo Aero Corporation, Trollhättan, Sweden.
    Kloosterman, Arjen
    National Aerospace Laboratory NLR, Gas Turbines & Structural Integrity Department, Amsterdam, The Netherlands.
    Meverel, Remy
    ONERA, Chatillon Cedex, France.
    Feist, Jörg
    Southside Thermal Sciences (STS) Ltd, London, United Kingdom.
    Nicholls, John
    Cranfield University, Cranfield, United Kingdom.
    Recent activities in the field of thermal barrier coatings including burner rig testing in the european union.2008Inngår i: Advanced Engineering Materials, ISSN 1438-1656, E-ISSN 1527-2648, Vol. 10, nr 10, s. 907-921Artikkel, forskningsoversikt (Annet vitenskapelig)
  • 124.
    Vijay, S.
    et al.
    BITS Pilani, Pilani, India.
    Roy, B.
    BITS Pilani, Pilani, India.
    Markocsan, Nicolaie
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Lyphout, Christophe
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Wetting properties of ceramic reinforced metal matrix composites on varied roughness profiles2017Inngår i: Proceedings of the International Thermal Spray Conference & Exposition (ITSC 2017), New York: Curran Associates, Inc. , 2017, Vol. 1, s. 537-542Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Superhydrophobic surfaces are of great importance in many industrial applications, especially where components are exposed to wet environments and low temperatures.Texturing of surfaces to reach superhydrophobicity can be achieved by thermal spraying technology, which is an attractive coating method as it is cheap, flexible and can employ a large range of feedstock materials. In this study, ceramic reinforced metal matrix composite (WC-CoCr) powders were sprayed using High Velocity Air Fuel method. They were varied based on their powder parameters such as carbide grain size, binder grain size and powder strength. The purpose was to investigate their hydrophobic characteristics and how these are influenced by different roughness profiles. The wetting properties such as contact angle and contact angle hysteresis were first investigated for the as-sprayed coatings. The roughness properties and Hausdorff Dimension were then related to the wetting properties. Aside from as-sprayed coatings, the effect of roughness and inherent wetting characteristics were studied by investigating the coating surface after grit blasting and polishing. Results show that powder parameters can lead to designing surfaces with higher surface roughnesses and thus having higher contact angles. It was also shown that surface composition of cermets has an impact on wettability, with the binder accounting for wetting characteristics and carbides accounting for roughness. 

  • 125.
    Vijay, Sudarshan
    et al.
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Markocsan, Nicolaie
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Lyphout, Christophe
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Roy, B.
    Investigation of wetting properties of ceramic reinforced metal matrixc omposites on varied roughness profiles2017Konferansepaper (Annet vitenskapelig)
  • 126.
    Vijay, Sudarshan
    et al.
    Birla Institute of Technology and Science-Pilani (BITS-Pilani), Pilani, India.
    Wang, Litian
    Østfold University College, Fredrikstad, Norway.
    Lyphout, Christophe
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Nylén, Per
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Markocsan, Nicolaie
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Surface characteristics investigation of HVAF sprayed cermet coatings2019Inngår i: Applied Surface Science, ISSN 0169-4332, E-ISSN 1873-5584, Vol. 493, s. 956-962Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Superhydrophobic surfaces that are durable and can be easily manufactured are of high interest for many industrial applications. Measuring and understanding roughness in the context of superhydrophobicity is the first step in creation of a surface that does not require activation to be hydrophobic. In this study, the as sprayed surface of different cermet (WC-10Co4Cr and Cr3C2-25Ni20Cr) coatings produced by High Velocity Air Fuel (HVAF) spraying – have been investigated to assess their wetting ability. In order to address the challenges raised by the specific roughness profile of thermal spray surfaces, two routes have been adapted and used for surface characteristics analysis i.e. statistical and fractal. Results show that both methods have a strong correlation to wettability. Roughness parameters Sdq and Sdr show good correlation with advancing contact angle. Hausdorff Dimension of a sub-micrometer profile shows good relation with the contact angle and provides information for state of the droplet. To determine how to increase the contact angle of the coating surface, coating parameters such as CGS Density have been correlated with Hausdorff Dimension. Both methods provide good understanding in terms of wettability of rough cermet surfaces. © 2019 Elsevier B.V.

  • 127.
    Zhang, Pimin
    et al.
    Linköping University, Department of Management and Engineering, Linköping, SE-58183, Sweden.
    Sadeghi, Esmaeil
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Chen, Shula
    Linköping University, Department of Physics, Chemistry, and Biology, Linköping, SE-58183, Sweden.
    Li, Xin-Hai
    Siemens Industrial Turbomachinery AB, Finspång, SE-61283, Sweden.
    Markocsan, Nicolaie
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Joshi, Shrikant V.
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Forskningsmiljön produktionsteknik(PTW).
    Chen, Weimin
    Linköping University, Department of Physics, Chemistry, and Biology, Linköping, SE-58183, Sweden.
    Buyanova, Irina A.
    Linköping University, Department of Physics, Chemistry, and Biology, Linköping, SE-58183, Sweden.
    Peng, Ru L.in
    Linköping University, Department of Management and Engineering, Linköping, SE-58183, Sweden.
    Effects of surface finish on the initial oxidation of HVAF-sprayed NiCoCrAlY coatings2019Inngår i: Surface & Coatings Technology, ISSN 0257-8972, E-ISSN 1879-3347, Vol. 364, s. 43-56Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Oxide scale formed on HVAF-sprayed NiCoCrAlY coatings and the effect of surface treatment were investigated by a multi-approach study combining photo-stimulated luminescence, microstructural observation and mass gain. The initial oxidationbehaviour of as-sprayed, polished and shot-peened coatings at 1000 °C is studied. Both polished and shot-peened coatings exhibited superior performance due to rapid formation of α-Al2O3 fully covering the coating and suppressing the growth of transient alumina, assisted by a high density of α-Al2O3 nuclei on surface treatment induced defects. Moreover, the fast development of a two-layer alumina scale consisting of an inward-grown inner α-Al2O3 layer and an outer layer transformed from outward-grown transient alumina resulted in a higher oxide growth rate of the as-sprayed coating.

  • 128.
    Zhang, Pimin
    et al.
    Linköping University, Department of Management and Engineering, Linköping, Sweden.
    Sadeghimeresht, Esmaeil
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Peng, Ru Lin
    Linköping University, Department of Management and Engineering, Linköping, Sweden.
    Li, Xin-Hai
    Siemens Industrial Turbomachinery AB, Finspång, Sweden.
    Markocsan, Nicolaie
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Joshi, Shrikant
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Johansson, Sten
    Linköping University, Department of Management and Engineering, Linköping, Sweden.
    Isothermal oxidation behavior of HVAF-sprayed NiCoCrAlY coatings: Effect of surface treatment2017Inngår i: Proceedings of the International Thermal Spray Conference & Exposition (ITSC 2017), New York: Curran Associates, Inc , 2017, Vol. 1, s. 456-461Konferansepaper (Fagfellevurdert)
    Abstract [en]

    NiCoCrAlY coatings are widely used as bond coats for ceramic thermal barrier coatings (TBCs) andoxidation and corrosion protective overlay coatings in industrial gas turbines. High temperature oxidation behaviour of NiCoCrAlYs has a great influence on the coating performance and lifetime of TBCs. A promising route to decrease the oxidation rate of such coatings is post-coating surface modification which can facilitate formation of a uniform alumina scale with a considerably slower growth rate compared to the as-sprayed coatings. In this work, the effect of surface treatment by means of shot peening and laser surface melting (LSM) on the oxidation resistance of high velocity air-fuel (HVAF) sprayed NiCoCrAlY coatings was studied. Isothermal oxidation was carried out at 1000⁰C for 1000h. Results showed that the rough surface of as-sprayed HVAF sprayed coatings was significantly changed after shot peening and LSM treatment, with a compact and smooth appearance. After the exposure, the oxide scales formed on surface-treated NiCoCrAlY coatings showed different morphology and growth rate compared to those formed on as-sprayed coating surface. The oxidation behaviour of surface treated HVAF-sprayed NiCoCrAlY coatings were revealed and discussed.

  • 129.
    Zhang, Xun
    et al.
    The University of Manchester, Henry Moseley X-ray Imaging Facility, The Henry Royce Institute, School of Materials, M13 9PL, Manchester, United Kingdom.
    Li, Chun
    State Key Laboratory of Advanced Welding and Joining, Harbin Institute of Technology, Harbin, 150001, China; The University of Manchester, School of Materials, M13 9PL, Manchester, United Kingdom.
    Withers, Philip J.
    The University of Manchester, Henry Moseley X-ray Imaging Facility, The Henry Royce Institute, School of Materials, M13 9PL, Manchester, United Kingdom.
    Markocsan, Nicolaie
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT).
    Xiao, Ping
    The University of Manchester, School of Materials, M13 9PL, Manchester, United Kingdom.
    Determination of local residual stress in an air plasma spray thermal barrier coating (APS-TBC) by microscale ring coring using a picosecond laser2019Inngår i: Scripta Materialia, ISSN 1359-6462, E-ISSN 1872-8456, Vol. 167, s. 126-130Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A picosecond laser for incremental annular trench cutting is combined with digital image correlation (DIC) to extend the incremental ring-core method to the profiling of residual stress in thick (>100 μm) coatings. In this case the local residual stress in a TBC is depth profiled after exposure to 1150 °C for 190 h. The topcoat was found to be in compression with an average compressive stress of −94 ± 8 MPa which is representative of the stresses that would be generated elastically on cooling from a stress-free temperature of ~970 °C. The stress profile measurements have been validated by high-energy synchrotron X-ray diffraction measurements. © 2019

  • 130.
    Zhao, Y.
    et al.
    University of Manchester, School of Materials.
    Shinmi, A.
    University of Manchester, School of Materials.
    Zhao, X.
    University of Manchester, School of Materials.
    Withers, P. J.
    University of Manchester, School of Materials.
    Van Boxel, S.
    University of Manchester, School of Materials.
    Markocsan, Nicolaie
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avd för industriell produktion.
    Nylén, Per
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avd för industriell produktion.
    Xiao, Ping
    University of Manchester, School of Materials.
    Investigation of interfacial properties of atmospheric plasma sprayed thermal barrier coatings with four-point bending and computed tomography technique2012Inngår i: Surface and Coatings Technology, ISSN 0257-8972, Vol. 206, nr 23, s. 4922-4929Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A modified four-point bending test has been employed to investigate the interfacial toughness of atmospheric plasma sprayed (APS) yttria stabilised zirconia (YSZ) thermal barrier coatings (TBCs) after isothermal heat treatments at 1150°C. The delamination of the TBCs occurred mainly within the TBC, several to tens of microns above the interface between the TBC and bond coat. X-ray diffraction analysis revealed that the TBC was mainly tetragonal in structure with a small amount of the monoclinic phase. The calculated energy release rate increased from ~50J/m -2 for as-sprayed TBCs to ~120J/m -2 for the TBCs exposed at 1150°C for 200h with a loading phase angle about 42°. This may be attributed to the sintering of the TBC. X-ray micro-tomography was used to track in 3D the evolution of the TBC microstructure non-destructively at a single location as a function of thermal exposure time. This revealed how various types of imperfections develop near the interface after exposure. The 3D interface was reconstructed and showed no significant change in the interfacial roughness after thermal exposure. © 2012 Elsevier B.V.

123 101 - 130 of 130
RefereraExporteraLink til resultatlisten
Permanent link
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annet format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annet språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf