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Joshi, S. V. & Nylén, P. (2019). Advanced Coatings by Thermal Spray Processes. Technologies, 7(4), Article ID 79.
Open this publication in new window or tab >>Advanced Coatings by Thermal Spray Processes
2019 (English)In: Technologies, Vol. 7, no 4, article id 79Article in journal (Refereed) Published
Abstract [en]

Coatings are pivotal in combating problems of premature component degradation in aggressive industrial environments and constitute a strategic area for continued development. Thermal spray (TS) coatings offer distinct advantages by combining versatility, cost-effectiveness, and the ability to coat complex geometries without constraints of other in-chamber processes. Consequently, TS techniques like high-velocity oxy-fuel (HVOF) and atmospheric plasma spray (APS) are industrially well-accepted. However, they have reached limits of their capabilities while expectations from coatings progressively increase in pursuit of enhanced efficiency and productivity. Two emerging TS variants, namely high-velocity air-fuel (HVAF) and liquid feedstock thermal spraying, offer attractive pathways to realize high-performance surfaces superior to those hitherto achievable. Supersonic HVAF spraying provides highly adherent coatings with negligible porosity and its low processing temperature also ensures insignificant thermal ‘damage’ (oxidation, decarburization, etc.) to the starting material. On the other hand, liquid feedstock derived TS coatings, deposited using suspensions of fine particles (100 nm–5 µm) or solution precursors, permits the production of coatings with novel microstructures and diverse application-specific architectures. The possibility of hybrid processing, combining liquid and powder feedstock, provides further opportunities to fine tune the properties of functional surfaces. These new approaches are discussed along with some illustrative examples.

Keywords
coatings, high-velocity air-fuel, plasma spray, solution precursor, suspension
National Category
Manufacturing, Surface and Joining Technology
Research subject
ENGINEERING, Manufacturing and materials engineering
Identifiers
urn:nbn:se:hv:diva-14702 (URN)10.3390/technologies7040079 (DOI)
Available from: 2019-11-15 Created: 2019-11-15 Last updated: 2019-11-15
Mahade, S., Curry, N., Jonnalagadda, K. P., Peng, R. L., Markocsan, N. & Nylén, P. (2019). Influence of YSZ layer thickness on the durability of gadolinium zirconate/YSZ double-layered thermal barrier coatings produced by suspension plasma spray. Surface & Coatings Technology, 357, 456-465
Open this publication in new window or tab >>Influence of YSZ layer thickness on the durability of gadolinium zirconate/YSZ double-layered thermal barrier coatings produced by suspension plasma spray
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2019 (English)In: Surface & Coatings Technology, ISSN 0257-8972, E-ISSN 1879-3347, Vol. 357, p. 456-465Article in journal (Refereed) Published
Abstract [en]

In this work, three double layered thermal barrier coating (TBC) variations with different gadolinium zirconate (GZ) and YSZ thickness (400GZ/100YSZ, 250GZ/250YSZ and 100GZ/400YSZ respectively, where the prefixed numbers before GZ and YSZ represent the layer thickness in μm), were produced by suspension plasma spray (SPS) process. The objective was to investigate the influence of YSZ thickness on the thermal conductivity and thermal shock lifetime of the GZ/YSZ double layered TBCs. The as sprayed TBCs were characterized using SEM, XRD and porosity measurements. Thermal diffusivity measurements were made using laser flash analysis and the thermal conductivity of the TBCs was calculated. The double layered TBC with the lowest YSZ (400GZ/100YSZ) thickness showed lower thermal diffusivity and thermal conductivity. The double layered TBCs were subjected to thermal shock test at a TBC surface temperature of 1350 °C. Results indicate that the TBC with a higher YSZ thickness (100GZ/400YSZ) showed inferior thermal shock lifetime whereas the TBCs with low YSZ thickness showed comparatively higher thermal shock lifetimes. Failure of the TBCs after thermal shock test was analyzed using SEM and XRD to gain further insights.

Place, publisher, year, edition, pages
Elsevier, 2019
Keywords
Gadolinium; Plasma jets; Plasma spraying; Thermal conductivity; Thermal shock; X ray diffraction; Yttria stabilized zirconia; Yttrium oxide; Zirconia, Diffusivity measurements; Double layered; Gadolinium zirconate; Layer thickness; Porosity measurement; Surface temperatures; Suspension plasma sprays; Thermal barrier coating (TBC), Thermal barrier coatings
National Category
Manufacturing, Surface and Joining Technology
Research subject
ENGINEERING, Manufacturing and materials engineering; Production Technology
Identifiers
urn:nbn:se:hv:diva-13106 (URN)10.1016/j.surfcoat.2018.10.046 (DOI)000455691100067 ()2-s2.0-85055204877 (Scopus ID)
Funder
Knowledge Foundation, 20140130
Available from: 2018-11-07 Created: 2018-11-07 Last updated: 2019-02-04Bibliographically approved
Chen, Y., Zhang, X., Zhao, X., Markocsan, N., Nylén, P. & Xiao, P. (2019). Measurements of elastic modulus and fracture toughness of an air plasma sprayed thermal barrier coating using micro-cantilever bending. Surface & Coatings Technology, 374, 12-20
Open this publication in new window or tab >>Measurements of elastic modulus and fracture toughness of an air plasma sprayed thermal barrier coating using micro-cantilever bending
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2019 (English)In: Surface & Coatings Technology, ISSN 0257-8972, E-ISSN 1879-3347, Vol. 374, p. 12-20Article in journal (Refereed) Published
Abstract [en]

The elastic modulus and fracture toughness of an air plasma sprayed thermal barrier coating (APS TBC) were measured using the micro-cantilever bending technique. The micro-cantilevers were machined by a focused ion beam with their central arms either parallel or normal to the bond coat/topcoat interface. Such orientations allowed direct measurements of both the in-plane and out-of-plane elastic moduli as well as mode I fracture toughness by bending. The calculated elastic modulus along the in-plane and out-of-plane direction is 144 GPa and 110 GPa, respectively, suggesting that the APS TBC is elastically anisotropic at microscale. The derived mode I fracture toughness along the plane parallel to the interface is 0.40 MPam. This relatively low toughness reflects the weak fracture resistance of the highly-flawed APS for short cracks at microscale. The measurements in this study can be incorporated into micromechanical life time prediction models of the APS TBCs. © 2019 Elsevier B.V.

Keywords
Elastic moduli; Ion beams; Microstructure; Nanocantilevers; Plasma jets; Plasma spraying; Thermal barrier coatings, Air plasma sprayed thermal barrier coatings; Direct measurement; Lifetime prediction; Measurements of; Micro-cantilevers; Micro-mechanical; Mode-i fracture toughness; Out-of-plane direction, Fracture toughness
National Category
Manufacturing, Surface and Joining Technology
Research subject
ENGINEERING, Manufacturing and materials engineering; Production Technology
Identifiers
urn:nbn:se:hv:diva-14455 (URN)10.1016/j.surfcoat.2019.05.031 (DOI)000486360000002 ()2-s2.0-85066829982 (Scopus ID)
Available from: 2019-10-01 Created: 2019-10-01 Last updated: 2019-11-25Bibliographically approved
Kumara, C., Segerstark, A., Hanning, F., Dixit, N., Joshi, S. V., Moverare, J. & Nylén, P. (2019). Microstructure modelling of laser metal powder directed energy deposition of alloy 718. Additive Manufacturing, 25, 357-364
Open this publication in new window or tab >>Microstructure modelling of laser metal powder directed energy deposition of alloy 718
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2019 (English)In: Additive Manufacturing, ISSN 2214-8604, Vol. 25, p. 357-364Article in journal (Refereed) Published
Abstract [en]

A multi-component and multi-phase-field modelling approach, combined with transformation kinetics modelling, was used to model microstructure evolution during laser metal powder directed energy deposition of Alloy 718 and subsequent heat treatments. Experimental temperature measurements were utilised to predict microstructural evolution during successive addition of layers. Segregation of alloying elements as well as formation of Laves and δ phase was specifically modelled. The predicted elemental concentrations were then used in transformation kinetics to estimate changes in Continuous Cooling Transformation (CCT) and Time Temperature Transformation (TTT) diagrams for Alloy 718. Modelling results showed good agreement with experimentally observed phase evolution within the microstructure. The results indicate that the approach can be a valuable tool, both for improving process understanding and for process development including subsequent heat treatment.

Place, publisher, year, edition, pages
Elsevier, 2019
Keywords
Phase-field, DED, Heat treatment, Thermal cycle, Modelling
National Category
Manufacturing, Surface and Joining Technology
Research subject
Production Technology; ENGINEERING, Manufacturing and materials engineering
Identifiers
urn:nbn:se:hv:diva-13195 (URN)10.1016/j.addma.2018.11.024 (DOI)000456378800034 ()2-s2.0-85057193791 (Scopus ID)
Funder
Knowledge Foundation
Note

Funders: European Regional Development Fund for project 3Dprint

Available from: 2018-12-12 Created: 2018-12-12 Last updated: 2019-04-03Bibliographically approved
Kumara, C., Deng, D., Hanning, F., Raanes, M., Moverare, J. & Nylén, P. (2019). Predicting the Microstructural Evolution of Electron Beam Melting of Alloy 718 with Phase-Field Modeling. Metallurgical and Materials Transactions. A, 50A(5), 527-2537
Open this publication in new window or tab >>Predicting the Microstructural Evolution of Electron Beam Melting of Alloy 718 with Phase-Field Modeling
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2019 (English)In: Metallurgical and Materials Transactions. A, ISSN 1073-5623, E-ISSN 1543-1940, Vol. 50A, no 5, p. 527-2537Article in journal (Refereed) Published
Abstract [en]

Electron beam melting (EBM) is a powder bed additive manufacturing process where a powder material is melted selectively in a layer-by-layer approach using an electron beam. EBM has some unique features during the manufacture of components with high-performance superalloys that are commonly used in gas turbines such as Alloy 718. EBM has a high deposition rate due to its high beam energy and speed, comparatively low residual stresses, and limited problems with oxidation. However, due to the layer-by-layer melting approach and high powder bed temperature, the as-built EBM Alloy 718 exhibits a microstructural gradient starting from the top of the sample. In this study, we conducted modeling to obtain a deeper understanding of microstructural development during EBM and the homogenization that occurs during manufacturing with Alloy 718. A multicomponent phase-field modeling approach was combined with transformation kinetic modeling to predict the microstructural gradient and the results were compared with experimental observations. In particular, we investigated the segregation of elements during solidification and the subsequent "in situ" homogenization heat treatment at the elevated powder bed temperature. The predicted elemental composition was then used for thermodynamic modeling to predict the changes in the continuous cooling transformation and time-temperature transformation diagrams for Alloy 718, which helped to explain the observed phase evolution within the microstructure. The results indicate that the proposed approach can be employed as a valuable tool for understanding processes and for process development, including post-heat treatments. © 2019, The Author(s).

Keywords
3D printers; Deposition rates; Electron beam melting; Electron beams; Forecasting; Gas turbines; Microstructural evolution; Solid solutions; Temperature, Additive manufacturing process; Continuous cooling transformation; Elemental compositions; Layer-by-layer approaches; Microstructural development; Microstructural gradients; Transformation diagrams; Transformation kinetics, Heat treatment
National Category
Manufacturing, Surface and Joining Technology
Research subject
ENGINEERING, Manufacturing and materials engineering
Identifiers
urn:nbn:se:hv:diva-13756 (URN)10.1007/s11661-019-05163-7 (DOI)000463991300038 ()2-s2.0-85062604965 (Scopus ID)
Funder
Knowledge FoundationEuropean Regional Development Fund (ERDF)
Available from: 2019-05-10 Created: 2019-05-10 Last updated: 2019-07-25Bibliographically approved
Vijay, S., Wang, L., Lyphout, C., Nylén, P. & Markocsan, N. (2019). Surface characteristics investigation of HVAF sprayed cermet coatings. Applied Surface Science, 493, 956-962
Open this publication in new window or tab >>Surface characteristics investigation of HVAF sprayed cermet coatings
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2019 (English)In: Applied Surface Science, ISSN 0169-4332, E-ISSN 1873-5584, Vol. 493, p. 956-962Article in journal (Refereed) Published
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.

Keywords
Air; Cermets; Contact angle; Fractals; Hydrophobicity; Sprayed coatings; Statistical methods; Surface roughness, Advancing contact angle; Cermet coatings; Fractal analysis; High velocity air fuels; Hydrophobic surfaces; Roughness parameters; Super-hydrophobic surfaces; Surface characteristics, Wetting
National Category
Manufacturing, Surface and Joining Technology
Research subject
ENGINEERING, Manufacturing and materials engineering; Production Technology
Identifiers
urn:nbn:se:hv:diva-14483 (URN)10.1016/j.apsusc.2019.07.079 (DOI)2-s2.0-85069570632 (Scopus ID)
Available from: 2019-10-02 Created: 2019-10-02 Last updated: 2019-11-12Bibliographically approved
Mahade, S., Zhou, D., Curry, N., Markocsan, N., Nylén, P. & Vassen, R. (2019). Tailored microstructures of gadolinium zirconate/YSZ multi-layered thermal barrier coatings produced by suspension plasma spray: Durability and erosion testing. Journal of Materials Processing Technology, 264, 283-294
Open this publication in new window or tab >>Tailored microstructures of gadolinium zirconate/YSZ multi-layered thermal barrier coatings produced by suspension plasma spray: Durability and erosion testing
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2019 (English)In: Journal of Materials Processing Technology, ISSN 0924-0136, E-ISSN 1873-4774, Vol. 264, p. 283-294Article in journal (Refereed) Published
Abstract [en]

This work employed an axial suspension plasma spray (SPS) process to deposit two different gadolinium zirconate (GZ) based triple layered thermal barrier coatings (TBCs). The first was a 'layered' TBC (GZ dense/GZ/YSZ) where the base layer was YSZ, intermediate layer was a relatively porous GZ and the top layer was a relatively dense GZ. The second triple layered TBC was a 'composite' TBC (GZ dense/GZ + YSZ/YSZ) comprising of an YSZ base layer, a GZ + YSZ intermediate layer and a dense GZ top layer. The as sprayed TBCs (layered and composite) were characterized using SEM/EDS and XRD. Two different methods (water intrusion and image analysis) were used to measure the porosity content of the as sprayed TBCs. Fracture toughness measurements were made on the intermediate layers (GZ + YSZ layer of the composite TBC and porous GZ layer of the layered TBC respectively) using micro indentation tests. The GZ + YSZ layer in the composite TBC was shown to have a slightly higher fracture toughness than the relatively porous GZ layer in the layered TBC. Erosion performance of the as sprayed TBCs was evaluated at room temperature where the composite TBC showed higher erosion resistance than the layered TBC. However, in the burner rig test conducted at 1400 °C, the layered TBC showed higher thermal cyclic lifetime than the composite TBC. Failure analysis of the thermally cycled and eroded TBCs was performed using SEM and XRD. © 2018 Elsevier B.V.

Place, publisher, year, edition, pages
Elsevier, 2019
Keywords
Composite materials, Durability, Erosion, Failure (mechanical), Gadolinium, Plasma jets, Plasma spraying, Thermal barrier coatings, X ray diffraction, Yttria stabilized zirconia, Burner rig, Erosion resistance, Fracture toughness measurements, Gadolinium zirconate, Intermediate layers, Micro-indentation tests, Suspension plasma sprays, Thermal barrier coating (TBCs), Fracture toughness
National Category
Manufacturing, Surface and Joining Technology
Research subject
ENGINEERING, Manufacturing and materials engineering; Production Technology
Identifiers
urn:nbn:se:hv:diva-13041 (URN)10.1016/j.jmatprotec.2018.09.016 (DOI)000450135400028 ()2-s2.0-85053777782 (Scopus ID)
Funder
Knowledge Foundation, 20140130
Available from: 2018-10-29 Created: 2018-10-29 Last updated: 2018-12-20Bibliographically approved
Mahade, S., Ruelle, C., Curry, N., Holmberg, J., Björklund, S., Markocsan, N. & Nylén, P. (2019). Understanding the effect of material composition and microstructural design on the erosion behavior of plasma sprayed thermal barrier coatings. Applied Surface Science, 488, 170-184
Open this publication in new window or tab >>Understanding the effect of material composition and microstructural design on the erosion behavior of plasma sprayed thermal barrier coatings
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2019 (English)In: Applied Surface Science, ISSN 0169-4332, E-ISSN 1873-5584, Vol. 488, p. 170-184Article in journal (Refereed) Published
Abstract [en]

In this work, three different TBC compositions comprising of yttria partially stabilized zirconia (8YSZ), yttria fully stabilized zirconia (48YSZ) and gadolinium zirconate (GZ) respectively, were processed by suspension plasma spray (SPS) to obtain columnar microstructured TBCs. Additionally, for comparison, lamellar microstructured, 7YSZ TBC was deposited by air plasma spray (APS) process. SEM analysis was carried out to investigate the microstructure and white light interferometry was used to evaluate the surface morphology of the as-sprayed TBCs. Porosity measurements were made using water intrusion and image analysis methods and it was observed that the SPS-YSZ and APS-YSZ TBCs showed higher porosity content than SPS-GZ and SPS-48YSZ. The as-sprayed TBC variations (APS-YSZ, SPS-YSZ, SPS-GZ, and SPS-48YSZ) were subjected to erosion test. Results indicate that the erosion resistance of APS-YSZ TBC was inferior to the SPS-YSZ, SPS-GZ and SPS-48YSZ TBCs respectively. Among the SPS processed TBCs, SPS-YSZ showed the highest erosion resistance whereas the SPS-48YSZ showed the lowest erosion resistance. SEM analysis of the eroded TBCs (cross section and surface morphology) was performed to gain further insights on their erosion behavior. Based on the erosion results and post erosion SEM analysis, erosion mechanisms for splat like microstructured APS TBC and columnar microstructured SPS TBCs were proposed. The findings from this work provide new insights on the erosion mechanisms of columnar microstructured TBCs and lamellar microstructured TBCs deposited by plasma spray. © 2019 Elsevier B.V.

Keywords
Erosion; Microstructure; Morphology; Plasma jets; Porosity; Sprayed coatings; Surface morphology; Thermal barrier coatings; Yttria stabilized zirconia; Yttrium oxide; Zirconia, Atmospheric plasma spray; Gadolinium zirconate; Stabilized zirconia; Suspension plasma sprays; Yttria partially stabilized zirconia, Plasma spraying
National Category
Manufacturing, Surface and Joining Technology
Research subject
ENGINEERING, Manufacturing and materials engineering
Identifiers
urn:nbn:se:hv:diva-13987 (URN)10.1016/j.apsusc.2019.05.245 (DOI)000472476200020 ()2-s2.0-85066427612 (Scopus ID)
Funder
Knowledge Foundation, 20140130
Available from: 2019-06-20 Created: 2019-06-20 Last updated: 2019-10-18Bibliographically approved
Mahade, S., Markocsan, N., Nylén, P. & Curry, N. (2018). Effect of YSZ thickness on the thermal cyclic fatigue performance of gadolinium zirconate/YSZ double layered TBCs. Paper presented at International Thermal Spray Conference, ITSC 2018; Orlando; United States; 7 May 2018 through 10 May 2018. Proceedings of the International Thermal Spray Conference, 79-83
Open this publication in new window or tab >>Effect of YSZ thickness on the thermal cyclic fatigue performance of gadolinium zirconate/YSZ double layered TBCs
2018 (English)In: Proceedings of the International Thermal Spray Conference, p. 79-83Article in journal (Refereed) Published
Abstract [en]

Thermal barrier coatings (TBCs) play a vital role in allowing the gas turbine engines to operate at high temperatures. With higher operating temperatures (>1200°C), the standard TBC material, 7-8wt. % Yttria Stabilized Zirconia (YSZ), is susceptible to CMAS (Calcium Magnesium Alumino Silicates) degradation and undesirable phase transformation. New TBC materials such as gadolinium zirconate (GZ) have shown to be capable of overcoming the challenges faced by YSZ. However, GZ has inferior fracture toughness relative to YSZ. In this work, three double layered TBC variations with different GZ and YSZ thickness respectively (400GZ/100YSZ, 250GZ/250YSZ and 100GZ/400GZ respectively, where the prefix numbers represent thickness in urn) were produced by suspension plasma spray (SPS) process. In all the three double layered TBC variations, the overall TBC thickness with GZ as the top layer and YSZ as the base layer was kept the same (500 urn). The objective was to investigate the influence of YSZ thickness on the thermal cyclic fatigue performance of GZ/YSZ double layered TBC. The as sprayed TBCs were characterized by SEM, XRD and porosity measurements and later subjected to thermal cyclic fatigue test at 1100°C. It was observed that the GZ/YSZ double layered TBC with lowest YSZ thickness (400GZ/100YSZ) showed higher thermal cyclic lifetime whereas the TBC with thicker YSZ layer (100GZ/400YSZ) showed lowest thermal cyclic fatigue lifetime. The failure analysis of the thermally cycled TBCs revealed similar failure modes, i.e. spallation of the top coat due to horizontal crack propagation within the thermally grown oxide (TGO). Furthermore, the ceramic top coats in all the three TBC variations after failure showed the widening of column gaps. © 2018 ASM International® All rights reserved.

Place, publisher, year, edition, pages
ASM International, 2018
Keywords
Failure modes; Fatigue testing; Fracture toughness; Gadolinium; Magnesium compounds; Plasma spraying; Silicates; Thermal barrier coatings; Thermal fatigue; Yttrium oxide; Zirconia, Gadolinium zirconate; Operating temperature; Porosity measurement; Suspension plasma sprays; Thermal barrier coating (TBCs); Thermal cyclic fatigue; Thermally grown oxide; Yttria-stabilized zirconias (YSZ), Yttria stabilized zirconia
National Category
Manufacturing, Surface and Joining Technology
Research subject
ENGINEERING, Manufacturing and materials engineering; Production Technology
Identifiers
urn:nbn:se:hv:diva-14481 (URN)2-s2.0-85068908628 (Scopus ID)
Conference
International Thermal Spray Conference, ITSC 2018; Orlando; United States; 7 May 2018 through 10 May 2018
Available from: 2019-10-02 Created: 2019-10-02 Last updated: 2019-10-28Bibliographically approved
Karimi Neghlani, P., Sadeghimeresht, E., Deng, D., Gruber, H., Andersson, J. & Nylen, P. (2018). Influence of build layout and orientation on microstructural characteristics of electron beam melted Alloy 718. The International Journal of Advanced Manufacturing Technology, 99(S1), 2903-2913
Open this publication in new window or tab >>Influence of build layout and orientation on microstructural characteristics of electron beam melted Alloy 718
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2018 (English)In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 99, no S1, p. 2903-2913Article in journal (Refereed) Published
Abstract [en]

Effects of build layout and orientation consisting of (a) height from the build plate (Z-axis), (b) distance between samples, and (c) location in the build plate (X-Y plane) on porosity, NbC fraction, and hardness in electron beam melted (EBM) Alloy 718 were studied. The as-built samples predominantly showed columnar structure with strong ˂001˃ crystallographic orientation parallel to the build direction, as well as NbC and ÎŽ-phase in inter-dendrites and grain boundaries. These microstructural characteristics were correlated with the thermal history, specifically cooling rate, resulted from the build layout and orientation parameters. The hardness and NbC fraction of the samples increased around 6% and 116%, respectively, as the height increased from 2 to 45 mm. Moreover, by increasing the height, formation of ÎŽ-phase was also enhanced associated with lower cooling rate in the samples built with a greater distance from the build plate. However, the porosity fraction was unaffected. Increasing the sample gap from 2 to 10 mm did not change the NbC fraction and hardness; however, the porosity fraction increased by 94%. The sample location in the build chamber influenced the porosity fraction, particularly in interior and exterior areas of the build plate. The hardness and NbC fraction were not dependent on the sample location in the build chamber. © 2018, The Author(s).

Keywords
3D printers, Cooling, Electron beam melting, Electron beams, Grain boundaries, Hardness, Location, Niobium compounds, Porosity, Alloy 718, Build direction, Columnar structures, Crystallographic orientations, Micro-structural characteristics, Micro-structural characterization, Orientation parameter, Sample location, Porous plates
National Category
Manufacturing, Surface and Joining Technology
Research subject
ENGINEERING, Manufacturing and materials engineering; Production Technology
Identifiers
urn:nbn:se:hv:diva-13043 (URN)10.1007/s00170-018-2621-6 (DOI)000452076900065 ()2-s2.0-85053670925 (Scopus ID)
Funder
European Regional Development Fund (ERDF)Knowledge Foundation
Note

First Online: 17 September 2018

Available from: 2018-10-29 Created: 2018-10-29 Last updated: 2019-05-28Bibliographically approved
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Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0001-7787-5444

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