Change search
Link to record
Permanent link

Direct link
Publications (10 of 26) Show all publications
Ganvir, A., Nagar, S., Markocsan, N. & Balani, K. (2021). Deposition of hydroxyapatite coatings by axial plasma spraying: Influence of feedstock characteristics on coating microstructure, phase content and mechanical properties. Journal of the European Ceramic Society, 41(8), 4637-4649
Open this publication in new window or tab >>Deposition of hydroxyapatite coatings by axial plasma spraying: Influence of feedstock characteristics on coating microstructure, phase content and mechanical properties
2021 (English)In: Journal of the European Ceramic Society, ISSN 0955-2219, E-ISSN 1873-619X, Vol. 41, no 8, p. 4637-4649Article in journal (Refereed) Published
Abstract [en]

Axial plasma spray is one of the thermal spray techniques to deposit multifunctional advanced coatings. The present work explores the use of this process to deposit thin, continuous, and adherent Ca5 (PO4)3OH (hydroxyapatite, HAp) coatings and characterize its microstructure, phases, hardness and adhesion strength. Three different suspension-deposited HAp coatings were investigated and compared with powder-deposited HAp coating on a Ti6Al4V substrate. The effect of mean solute particle size and solid-loading in the suspension has been explored on the evolution of microstructure, phase content and mechanical properties of axial suspension plasma sprayed (ASPS) coatings. Phase-characterization has shown retention of hydroxyapatite phase and coating crystallinity in the deposited coatings, whereas the adhesion strength of the HAp coating decreased from -40 MPa to -13 MPa when bioglass was added to the feedstock material. The lower solid load content and lower mean solute particle size in the suspension were found to be beneficial in achieving porous, rougher, and welladhering coatings. This work concludes that ASPS can potentially deposit thin HAp coatings (< 50 ?m) with high adhesion strength.

Place, publisher, year, edition, pages
Elsevier, 2021
Keywords
Axial plasma spraying; Suspensions; Phase degradation; Hydroxyapatite coatings; Microstructure; Adhesion strength
National Category
Manufacturing, Surface and Joining Technology
Research subject
Production Technology
Identifiers
urn:nbn:se:hv:diva-17227 (URN)10.1016/j.jeurceramsoc.2021.02.050 (DOI)000637514600001 ()2-s2.0-85103052625 (Scopus ID)
Note

Finacing: Swarnajayanti fellowship, DST, Govt. of India (DST/SJF/ETA-02-2016-17)

Available from: 2021-12-16 Created: 2021-12-16 Last updated: 2021-12-16
Ganvir, A., Goel, S., Govindarajan, S., Jahagirdar, A. R., Björklund, S., Klement, U. & Joshi, S. V. (2021). Tribological performance assessment of Al2O3-YSZ composite coatings deposited by hybrid powder-suspension plasma spraying. Surface & Coatings Technology, 409, 1-13, Article ID 126907.
Open this publication in new window or tab >>Tribological performance assessment of Al2O3-YSZ composite coatings deposited by hybrid powder-suspension plasma spraying
Show others...
2021 (English)In: Surface & Coatings Technology, ISSN 0257-8972, E-ISSN 1879-3347, Vol. 409, p. 1-13, article id 126907Article in journal (Refereed) Published
Abstract [en]

The advent of high-throughput plasma spray systems that allow axial feeding encourages the study of using liquid feedstock for various next-generation functional applications. The current study explores the benefit of such a plasma spray system to deposit hybrid powder-suspension Al2O3-YSZ ceramic matrix composite (CMC) coatings for tribological applications. The tribological performance of the hybrid processed CMC coatings was assessed using scratch, ball-on-plate wear and erosion tests and compared with that of monolithic powder-derived Al2O3 coatings. As-deposited and tribo-tested coatings were characterized using Scanning Electron Microscopy, X-ray Diffraction and Energy Dispersive Spectroscopy to analyse their microstructure and phase constitution. The results showed that the tribological performance of the hybrid powder-suspension Al2O3-YSZ CMC coating was significantly improved by enhancing the wear resistance under scratch, dry sliding ball-on-plate and erosion tests as compared to the conventional APS deposited monolithic Al2O3 coating. About 36% decrease in the dry sliding ball-on-plate specific wear rate and up to 50% decrease in the erosion wear rate was noted in the hybrid powder-suspension Al2O3-YSZ CMC coating as compared to the conventional APS deposited monolithic Al2O3 coating. The study concludes that the hybrid powder-suspension route can create CMC coatings with unique multi-length scale microstructures which can be attractive for combining different tribological attributes in the same coating system.

Place, publisher, year, edition, pages
Elsevier, 2021
Keywords
Hybrid; Axial plasma spray; Suspension; Powder; Tribology; Erosion; Scratch & wear
National Category
Tribology (Interacting Surfaces including Friction, Lubrication and Wear)
Research subject
Production Technology
Identifiers
urn:nbn:se:hv:diva-17236 (URN)10.1016/j.surfcoat.2021.126907 (DOI)000654045600066 ()2-s2.0-85100396405 (Scopus ID)
Funder
Swedish Energy Agency, P46393-1
Available from: 2021-12-16 Created: 2021-12-16 Last updated: 2021-12-16
Ganvir, A., Gupta, M. K., Kumar, N. & Markocsan, N. (2020). Effect of suspension characteristics on the performance of thermal barrier coatings deposited by suspension plasma spray. Ceramics International, 47(1), 272-283
Open this publication in new window or tab >>Effect of suspension characteristics on the performance of thermal barrier coatings deposited by suspension plasma spray
2020 (English)In: Ceramics International, ISSN 0272-8842, E-ISSN 1873-3956, Vol. 47, no 1, p. 272-283Article in journal (Refereed) Published
Abstract [en]

This paper investigates the influence of suspension characteristics on microstructure and performance of suspensions plasma sprayed (SPS) thermal barrier coatings (TBCs). Five suspensions were produced using various suspension characteristics, namely, type of solvent and solid load content, and the resultant suspensions were utilized to deposit five different TBCs under identical processing conditions. The produced TBCs were evaluated for their performance i.e. thermal conductivity, thermal cyclic fatigue (TCF) and thermal shock (TS) lifetime. This experimental study revealed that the differences in the microstructure of SPS TBCs produced using varied suspensions resulted in a wide-ranging overall TBC performance. All TBCs exhibited thermal conductivity lower than 1 W/(m. K) except water-ethanol mixed suspension produced TBC. The TS lifetime was also affected to a large extent where 10 wt % solid loaded ethanol and 25 wt % solid loaded water suspensions produced TBCs exhibited the highest and the lowest lifetime, respectively. On the contrary, TCF lifetime was not as significantly affected as thermal conductivity and TS lifetime, and all ethanol suspensions showed marginally better TCF lifetime than water and ethanol-water mixed suspensions deposited TBCs. © 2020

Place, publisher, year, edition, pages
Elsevier, 2020
Keywords
Ethanol; Microstructure; Plasma jets; Plasma spraying; Sprayed coatings; Suspensions (fluids); Thermal conductivity; Thermal fatigue, Ethanol-water; Mixed suspensions; Plasma sprayed; Processing condition; Suspension plasma sprays; Thermal barrier coating (TBCs); Thermal cyclic fatigue; Water suspensions, Thermal barrier coatings
National Category
Manufacturing, Surface and Joining Technology
Research subject
Production Technology
Identifiers
urn:nbn:se:hv:diva-15773 (URN)10.1016/j.ceramint.2020.08.131 (DOI)000589661400004 ()2-s2.0-85089570648 (Scopus ID)
Funder
Region Västra Götaland, RUN 612-0974-13
Available from: 2020-09-04 Created: 2020-09-04 Last updated: 2021-02-09Bibliographically approved
Zafer, Y. E., Goel, S., Ganvir, A., Jansson, A. & Joshi, S. V. (2020). Encapsulation of Electron Beam Melting Produced Alloy 718 to Reduce Surface Connected Defects by Hot Isostatic Pressing. Materials, 13(5), Article ID 1226.
Open this publication in new window or tab >>Encapsulation of Electron Beam Melting Produced Alloy 718 to Reduce Surface Connected Defects by Hot Isostatic Pressing
Show others...
2020 (English)In: Materials, ISSN 1996-1944, E-ISSN 1996-1944, Vol. 13, no 5, article id 1226Article in journal (Refereed) Published
Abstract [en]

Defects in electron beam melting (EBM) manufactured Alloy 718 are inevitable to some extent, and are of concern as they can degrade mechanical properties of the material. Therefore, EBM-manufactured Alloy 718 is typically subjected to post-treatment to improve the properties of the as-built material. Although hot isostatic pressing (HIPing) is usually employed to close the defects, it is widely known that HIPing cannot close open-to-surface defects. Therefore, in this work, a hypothesis is formulated that if the surface of the EBM-manufactured specimen is suitably coated to encapsulate the EBM-manufactured specimen, then HIPing can be effective in healing such surface-connected defects. The EBM-manufactured Alloy 718 specimens were coated by high-velocity air fuel (HVAF) spraying using Alloy 718 powder prior to HIPing to evaluate the above approach. X-ray computed tomography (XCT) analysis of the defects in the same coated sample before and after HIPing showed that some of the defects connected to the EBM specimen surface were effectively encapsulated by the coating, as they were closed after HIPing. However, some of these surface-connected defects were retained. The reason for such remnant defects is attributed to the presence of interconnected pathways between the ambient and the original as-built surface of the EBM specimen, as the specimens were not coated on all sides. These pathways were also exaggerated by the high surface roughness of the EBM material and could have provided an additional path for argon infiltration, apart from the uncoated sides, thereby hindering complete densification of the specimen during HIPing.

National Category
Manufacturing, Surface and Joining Technology
Identifiers
urn:nbn:se:hv:diva-15061 (URN)10.3390/ma13051226 (DOI)000524060200204 ()2-s2.0-85092028472 (Scopus ID)
Available from: 2020-03-25 Created: 2020-03-25 Last updated: 2021-02-09
Ganvir, A., Björklund, S., Yao, Y., Vadali, S. V. .., Klement, U. & Joshi, S. V. (2019). A facile approach to deposit graphenaceous composite coatings by suspension plasma spraying. Coatings, 9(3), Article ID 171.
Open this publication in new window or tab >>A facile approach to deposit graphenaceous composite coatings by suspension plasma spraying
Show others...
2019 (English)In: Coatings, ISSN 2079-6412, Vol. 9, no 3, article id 171Article in journal (Refereed) Published
Abstract [en]

This paper demonstrates, for the first time ever, the deposition of graphenaceous composite coatings using an easy, yet robust, suspension plasma spraying (SPS) process. As a case study, a composite coating comprising 8 wt.% of yttria-stabilized-zirconia (8YSZ) and reinforced with graphene oxide (GO) was deposited on a steel substrate. The coatings were sprayed using an 8YSZ-GO mixed suspension with varied plasma spray parameters. Establishing the possibility of retaining the graphene in a ceramic matrix using SPS was of specific interest. Electron microscopy and Raman spectroscopy confirmed the presence of graphenaceous material distributed throughout the coating in the 8YSZ matrix. The experimental results discussed in this work confirm that SPS is an immensely attractive pathway to incorporate a graphenaceous material into virtually any matrix material and can potentially have major implications in enabling the deposition of large-area graphene-containing coatings for diverse functional applications. © 2019 by the authors.

National Category
Manufacturing, Surface and Joining Technology
Research subject
ENGINEERING, Manufacturing and materials engineering
Identifiers
urn:nbn:se:hv:diva-13737 (URN)10.3390/coatings9030171 (DOI)000465608700002 ()2-s2.0-85062495390 (Scopus ID)
Available from: 2019-03-21 Created: 2019-03-21 Last updated: 2020-02-04
Hameed, P., Gopal, V., Björklund, S., Ganvir, A., Sen, D., Markocsan, N. & Manivasagam, G. (2019). Axial Suspension Plasma Spraying: An ultimate technique to tailor Ti6Al4V surface with HAp for orthopaedic applications. Colloids and Surfaces B: Biointerfaces, 173, 806-815
Open this publication in new window or tab >>Axial Suspension Plasma Spraying: An ultimate technique to tailor Ti6Al4V surface with HAp for orthopaedic applications
Show others...
2019 (English)In: Colloids and Surfaces B: Biointerfaces, ISSN 0927-7765, E-ISSN 1873-4367, Vol. 173, p. 806-815Article in journal (Refereed) Published
Abstract [en]

Dissolution of atmospheric plasma sprayed (APS) hydroxyapatite (HAp) coatings on Ti-6Al-4 V medical implants have always been a challenge to overcome in the field of biomedical industry. In the present work, an attempt has been made to develop a HAp coating using a novel thermal spray process called axial suspension plasma spraying (SPS), which leads to thin adherent coatings. Two HAp coatings fabricated by APS (P1 and P2) and four SPS HAp coatings (S1, S2, S3 and S4) produced with varying spraying parameters were characterized in terms of (1) microstructure, porosity, hardness, adhesion strength, contact angle and phase purity; (2) corrosion resistance in 10% Fetal bovine serum (FBS); (3) in-vitro cell adherence and cell viability using human umbilical cord blood-derived mesenchymal stem cells (hMSCs). Amongst different APS and SPS coatings, P1 and S3 exhibited superior properties. S3 coating developed using SPS exhibited 1.3 times higher adhesion strength when compared to APS coating (P1) and 9.5 times higher corrosion resistance than P1. In addition, both S3 and P1 exhibited comparatively higher biocompatibility as evidenced by the presence of more than 92% viable hMSCs. © 2018 Elsevier B.V.

Keywords
Adhesion; Aluminum alloys; Aluminum coatings; Aluminum corrosion; Atmospheric corrosion; Biocompatibility; Bond strength (materials); Cell adhesion; Cell culture; Contact angle; Corrosion resistance; Corrosion resistant coatings; Corrosive effects; Hydroxyapatite; Mammals; Phase shifters; Plasma jets; Sprayed coatings; Stem cells; Ternary alloys; Thermal spraying; Titanium alloys; Vanadium alloys, Atmospheric plasma spraying; Corrosion studies; hMSCs; Suspension plasma spraying; Ti-6 Al-4 V, Plasma spraying
National Category
Manufacturing, Surface and Joining Technology
Research subject
ENGINEERING, Manufacturing and materials engineering; Production Technology
Identifiers
urn:nbn:se:hv:diva-13115 (URN)10.1016/j.colsurfb.2018.10.071 (DOI)000454377300095 ()30551296 (PubMedID)2-s2.0-85055725408 (Scopus ID)
Note

Available online 26 October 2018.

Available from: 2018-11-12 Created: 2018-11-12 Last updated: 2020-02-05Bibliographically approved
Ganvir, A., Calinas, R. F., Markocsan, N., Curry, N. & Joshi, S. V. (2019). Experimental visualization of microstructure evolution during suspension plasma spraying of thermal barrier coatings. Journal of the European Ceramic Society, 39(2-3), 470-481
Open this publication in new window or tab >>Experimental visualization of microstructure evolution during suspension plasma spraying of thermal barrier coatings
Show others...
2019 (English)In: Journal of the European Ceramic Society, ISSN 0955-2219, E-ISSN 1873-619X, Vol. 39, no 2-3, p. 470-481Article in journal (Refereed) Published
Abstract [en]

This paper investigates the evolution of microstructure of thermal barrier coatings (TBCs) produced by suspension plasma spraying (SPS) through a careful experimental study. Understanding the influence of different suspension characteristics such as type of solvent, solid load content and median particle size on the ensuing TBC microstructure, as well as visualizing the early stages of coating build-up leading to formation of a columnar microstructure or otherwise, was of specific interest. Several SPS TBCs with different suspensions were deposited under identical conditions (same substrate, bond coat and plasma spray parameters). The experimental study clearly revealed the important role of suspension characteristics, namely surface tension, density and viscosity, on the final microstructure, with study of its progressive evolution providing invaluable insights. Variations in suspension properties manifest in the form of differences in droplet momentum and trajectory, which are found to be key determinants governing the resulting microstructure (e.g., lamellar/vertically cracked or columnar).

Keywords
Suspension plasma spraying, Thermal barrier coatings, Droplet momentum, Columnar microstructure, Microstructure evolution
National Category
Manufacturing, Surface and Joining Technology
Research subject
ENGINEERING, Manufacturing and materials engineering; Production Technology
Identifiers
urn:nbn:se:hv:diva-12948 (URN)10.1016/j.jeurceramsoc.2018.09.023 (DOI)000450379400042 ()2-s2.0-85053889817 (Scopus ID)
Funder
Region Västra Götaland, RUN 612-0974-13
Available from: 2018-10-26 Created: 2018-10-26 Last updated: 2020-02-04Bibliographically approved
Algenaid, W., Ganvir, A., Calinas, R. F., Varghese, J., Rajulapati, K. V. & Joshi, S. V. (2019). Influence of microstructure on the erosion behaviour of suspension plasma sprayed thermal barrier coatings. Surface & Coatings Technology, 375, 86-99
Open this publication in new window or tab >>Influence of microstructure on the erosion behaviour of suspension plasma sprayed thermal barrier coatings
Show others...
2019 (English)In: Surface & Coatings Technology, ISSN 0257-8972, E-ISSN 1879-3347, Vol. 375, p. 86-99Article in journal (Refereed) Published
Abstract [en]

Thermal barrier coatings (TBCs) are applied on the surface of hot parts of gas turbine engines to increase the turbine efficiency by providing thermal insulation and to protect the engine parts from the harsh environment. Typical degradation of TBCs can be attributed to bond coat oxidation, thermal stress etc. In addition to this, erosion can also lead to partial or complete removal of the TBCs especially when the engine operates under erosive environment such as flying over desert area, near active volcanic or offshore ocean environment. Suspension Plasma Spraying (SPS) is a promising technique for TBC applications by virtue of its ability to produce a strain-tolerant porous-columnar microstructure that combines the benefits of both electron beam physical vapor deposited (EB-PVD) as well as atmospheric plasma sprayed (APS) coatings. This work investigates the influence of various coating microstructures produced by SPS on their erosion behavior. Six different coatings with varied microstructures produced using different suspensions with distinct characteristics were studied and their erosion resistance was compared. Results showed significant influence of SPS TBCs microstructures on the erosion resistance. Furthermore, the erosion resistance of SPS TBCs showed a close correlation between fracture toughness and the erosion rate, higher fracture toughness favours superior erosion resistance. © 2019 Elsevier B.V.

Keywords
Engines; Erosion; Fracture toughness; Microstructure; Offshore oil well production; Plasma jets; Porosity; Silicon compounds; Sprayed coatings; Thermal barrier coatings; Thermal insulation, Atmospheric plasmas; Coating microstructures; Columnar microstructures; Physical vapor deposited; Plasma-sprayed thermal barrier coating; Suspension plasma spraying; Thermal barrier coating (TBCs); Turbine efficiency, Plasma spraying
National Category
Manufacturing, Surface and Joining Technology
Research subject
ENGINEERING, Manufacturing and materials engineering; Production Technology
Identifiers
urn:nbn:se:hv:diva-14462 (URN)10.1016/j.surfcoat.2019.06.075 (DOI)000488409900010 ()2-s2.0-85068658494 (Scopus ID)
Available from: 2019-10-01 Created: 2019-10-01 Last updated: 2020-01-30Bibliographically approved
Ganvir, A. (2018). Design of Suspension Plasma Sprayed Thermal Barrier Coatings. (Doctoral dissertation). Trollhättan: University West
Open this publication in new window or tab >>Design of Suspension Plasma Sprayed Thermal Barrier Coatings
2018 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Thermal barrier coatings (TBCs) are widely used on gas turbine components to provide thermal insulation, which in combination with advanced cooling, can enable the gas turbine to operate at significantly higher temperatures even above the melting temperature of the metallic components. There is a permanent need,mainly due to environmental reasons, to increase the combustion temperature inturbines, hence new TBC solutions are needed. By using a liquid feedstock in thermal spraying, new types of TBCs can be produced. Suspension plasma/flame or solution precursor plasma spraying are examples of techniques that can be utilized for liquid feedstock thermal spraying. This approach of using suspension and solution feedstock, which is an alternative to the conventional solid powder feedstock spraying, is gaining increasing research interest since it has been shown to be capable of producing coatings withsuperior performance. The objective of this research work was to identify relationships between process parameters, coating microstructure, thermal conductivity and lifetime in suspension plasma sprayed TBCs. A further objective was to utilize these relationships to enable tailoring of the TBC microstructure for superior performance compared to state-of-the-art TBC used in industry today, i.e. solid feedstock plasma sprayed TBCs. Different spraying techniques, namely suspension high velocity oxy fuel, solution precursor plasma and suspension plasma spraying (with axial and radial feeding) were explored and compared to solid feedstock plasma spraying. A variety of microstructures, such as highly porous, vertically cracked and columnar, were produced and investigated. It was shown that there are strong relationships between microstructure, thermo-mechanical properties and performance of the coatings. Specifically, axial suspension plasma spraying wasshown as a very promising technique to produce various microstructures as wellas highly durable coatings. Based on the experimental results, a tailored columnar microstructure design for a superior TBC performance is also proposed.

Place, publisher, year, edition, pages
Trollhättan: University West, 2018. p. 96
Series
PhD Thesis: University West ; 20
Keywords
Microstructure; Thermal Barrier Coatings; Axial Injection; Suspension Plasma Spraying; Porosity; Thermal Conductivity; Fracture Toughness; Lifetime
National Category
Manufacturing, Surface and Joining Technology
Research subject
Production Technology; ENGINEERING, Manufacturing and materials engineering
Identifiers
urn:nbn:se:hv:diva-12336 (URN)978-91-87531-92-7 (ISBN)978-91-87531-91-0 (ISBN)
Public defence
2018-06-15, F104, University West, Trollhättan, 10:15 (English)
Opponent
Supervisors
Available from: 2018-05-25 Created: 2018-05-23 Last updated: 2018-05-25
Ganvir, A., Vaidhyanathan, V., Markocsan, N., Gupta, M. K., Pala, Z. & Lukac, F. (2018). Failure analysis of thermally cycled columnar thermal barrier coatings produced by high-velocity-air fuel and axial-suspension-plasma spraying: A design perspective. Ceramics International, 44(3), 3161-3172
Open this publication in new window or tab >>Failure analysis of thermally cycled columnar thermal barrier coatings produced by high-velocity-air fuel and axial-suspension-plasma spraying: A design perspective
Show others...
2018 (English)In: Ceramics International, ISSN 0272-8842, E-ISSN 1873-3956, Vol. 44, no 3, p. 3161-3172Article in journal (Refereed) Published
Abstract [en]

Axial-suspension-plasma spraying (ASPS) is a fairly recent thermal spray technology which enables production of ceramic top coats in TBCs, incorporating simultaneously the properties of both the conventional-plasma sprayed (highly insulating porous structures) and electron-beam-physical-vapor-deposited (strain-tolerant columnar structures) top coats. TBCs are required to insulate the hot components in a gas turbine engine against high temperature and harsh operating conditions. Periodic heating and cooling of turbine engines during operation can create severe thermal cyclic fatigue conditions which can degrade the performance of these coatings eventually leading to the failure. An in-depth experimental investigation was performed to understand the failure behavior of columnar TBCs subjected to thermal cyclic fatigue (TCF) test at 1100 C. The study revealed that the TCF performance was influenced to an extent, by the top coat microstructure, but was primarily affected by the severity of thermally grown oxide (TGO) growth at the bond coat-top coat interface. Mixed failure modes comprising crack propagation through the bond coat-TGO interface, through TGO and within the top coat were identified. Based on the analysis of the experimental results and thorough discussion a novel design of microstructure for the high TCF performance columnar TBC is proposed. © 2017 Elsevier Ltd and Techna Group S.r.l.

Keywords
Air; Coatings; Engines; Gas turbines; Microstructure; Plasma jets; Plasma spraying; Sprayed coatings; Structural design; Suspensions (components); Thermal spraying, Columnar structures; Experimental investigations; High velocity air fuels; Physical vapor deposited; Suspension plasma spraying; Thermal cyclic fatigue; Thermal spray technology; Thermally grown oxide, Thermal barrier coatings
National Category
Manufacturing, Surface and Joining Technology
Research subject
ENGINEERING, Manufacturing and materials engineering
Identifiers
urn:nbn:se:hv:diva-11920 (URN)10.1016/j.ceramint.2017.11.084 (DOI)000423891900070 ()2-s2.0-85034822127 (Scopus ID)
Funder
Region Västra Götaland, RUN 612-0974-13
Available from: 2017-12-13 Created: 2017-12-13 Last updated: 2019-05-28Bibliographically approved
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0003-1897-0171

Search in DiVA

Show all publications