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Moradi, M., Meiabadi, S. & Kaplan, A. (2019). 3D Printed Parts with Honeycomb Internal Pattern by Fused Deposition Modelling: Experimental Characterization and Production Optimization. Metals and Materials International
Open this publication in new window or tab >>3D Printed Parts with Honeycomb Internal Pattern by Fused Deposition Modelling: Experimental Characterization and Production Optimization
2019 (English)In: Metals and Materials International, ISSN 1598-9623, E-ISSN 2005-4149Article in journal (Refereed) Epub ahead of print
Abstract [en]

In the present study additive manufacturing of Polylactic acid by fused deposition modeling were investigated based on statis-tical analysis. The honeycomb internal pattern was employed to build inside of specimens due to its remarkable capability to resist mechanical loads. Simplify 3D was utilized to slice the 3D model and to adjust fixed parameters. Layer thickness, infill percentage, and extruder temperature were considered as controlled variables, while maximum failure load (N), elongation at break (mm), part weight (g), and build time (min) were selected as output responses and analysed by response surface method. Analysis of variance results identified layer thickness as the major controlled variable for all responses. Interaction of infill percentage and extruder temperature had a significant influence on elongation at break and therefore, tough fracture of printed parts. The input parameters were optimized to materialize tow criteria; the first one was to rise maximum failure load and the second was to attain tough fracture and lessen build time and part weight at a time. Optimal solutions were examined by experimental fabrication to evaluate the efficiency of the optimization method. There was a good agreement between empirical results and response surface method predictions which confirmed the reliability of predictive models. The optimal setting to fulfill the first criterion could bring on a specimen with more than 1500 (N) maximum failure load and less than 9 (g) weight.

Place, publisher, year, edition, pages
Springer, 2019
Keywords
3D printing, Fused deposition modelling, Mechanical properties, Part weight, Response surface method
National Category
Other Mechanical Engineering
Research subject
Manufacturing Systems Engineering
Identifiers
urn:nbn:se:ltu:diva-73719 (URN)10.1007/s12540-019-00272-9 (DOI)
Available from: 2019-04-23 Created: 2019-04-23 Last updated: 2019-04-23
Bunaziv, I., Akselsen, O., Frostevarg, J. & Kaplan, A. (2019). Application of laser-arc hybrid welding of steel for low-temperature service. The International Journal of Advanced Manufacturing Technology, 102(5-8), 2601-2613
Open this publication in new window or tab >>Application of laser-arc hybrid welding of steel for low-temperature service
2019 (English)In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 102, no 5-8, p. 2601-2613Article in journal (Refereed) Published
Abstract [en]

Laser-arc hybrid welding (LAHW) is more often used in shipbuilding and oil and gas industries in recent years. Its popularity arises due to many advantages compared to conventional arc welding processes. The laser beam source is used to achieve much higher penetration depths. By adding filler wire to the process area, by means of an arc source, the mechanical properties can be improved, e.g. higher toughness at low temperatures. Therefore, LAHW is a perspective process for low-temperature service. Applicability of LAHW is under concern due to process stability and mechanical properties related to heterogeneous filler wire distribution through the whole weld metal in deep and narrow joints. This can cause reduced mechanical properties in the weld root as well as problems with solidification cracking. The fast cooling rate in the root provides hard and brittle microconstituents lowering toughness at low temperatures. Numerical simulations and experimental observations showed that an increase in heat input from the laser beam is an effective way to reduce the cooling rate, which is also possible by applying preheating.

Place, publisher, year, edition, pages
Springer, 2019
Keywords
Laser beam, Hybrid welding, Microstructure, Toughness, Numerical simulation
National Category
Manufacturing, Surface and Joining Technology
Research subject
Manufacturing Systems Engineering
Identifiers
urn:nbn:se:ltu:diva-73054 (URN)10.1007/s00170-019-03304-1 (DOI)000469002200116 ()2-s2.0-85061037205 (Scopus ID)
Note

Validerad;2019;Nivå 2;2019-06-20 (johcin)

Available from: 2019-02-27 Created: 2019-02-27 Last updated: 2019-06-20Bibliographically approved
Bunaziv, I., Akselsen, O. M., Frostevarg, J. & Kaplan, A. (2019). Correction to: Application of laser-arc hybrid welding of steel for low-temperature service. The International Journal of Advanced Manufacturing Technology, 102(5-8), 2615-2615
Open this publication in new window or tab >>Correction to: Application of laser-arc hybrid welding of steel for low-temperature service
2019 (English)In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 102, no 5-8, p. 2615-2615Article in journal (Refereed) Published
Abstract [en]

The original version of this article contained several mistakes. Due to technical problems at the typesetter, author corrections were not carried out. The original article has been corrected.

Place, publisher, year, edition, pages
Springer, 2019
Identifiers
urn:nbn:se:ltu:diva-73409 (URN)10.1007/s00170-019-03536-1 (DOI)
Note

The International Journal of Advanced Manufacturing Technology, 102, 5-8, 2601-2613, DOI: 10.1007/s00170-019-03304-1

Available from: 2019-04-03 Created: 2019-04-03 Last updated: 2019-06-20Bibliographically approved
Olsson, R., Powell, J., Palmquist, A., Brånemark, R., Frostevarg, J. & Kaplan, A. (2019). Formation of osseointegrating (bone integrating) surfaces on titanium by laser irradiation. Journal of laser applications, 31(2), Article ID 022508.
Open this publication in new window or tab >>Formation of osseointegrating (bone integrating) surfaces on titanium by laser irradiation
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2019 (English)In: Journal of laser applications, ISSN 1042-346X, E-ISSN 1938-1387, Vol. 31, no 2, article id 022508Article in journal (Refereed) Published
Abstract [en]

Pulsed lasers can be used to modify the surface of medical implants in order to accelerate bone growth (osseointegration). A surface covered in attached droplets with diameters between 1 and 20 μm is a beneficial surface for rapid osseointegration. This paper presents the results of an experimental program in which a broad range of laser parameters and different atmospheres were used to create different surface textures on titanium substrates, including the desired "attached droplet" topology. The resulting surfaces were analyzed by scanning electron microscopy and micro-computer tomography. The paper explains how different types of surfaces are created by the laser-material interaction under different conditions and focus characteristics. It is shown that optimization of the laser parameters results in a robust process, which produces a surface that is fundamentally different from those created by nonlaser methods.

Place, publisher, year, edition, pages
Laser Institute of America, 2019
National Category
Manufacturing, Surface and Joining Technology
Research subject
Manufacturing Systems Engineering
Identifiers
urn:nbn:se:ltu:diva-73825 (URN)10.2351/1.5096075 (DOI)2-s2.0-85064218607 (Scopus ID)
Note

Validerad;2019;Nivå 2;2019-05-03 (johcin)

Available from: 2019-05-03 Created: 2019-05-03 Last updated: 2019-06-03Bibliographically approved
Näsström, J., Brueckner, F. & Kaplan, A. (2019). Laser enhancement of wire arc additive manufacturing. Paper presented at Proceedings of the International Congress of Applications of Lasers & Electro-Optics (ICALEO® 2018). Journal of laser applications, 31(2), Article ID 022307.
Open this publication in new window or tab >>Laser enhancement of wire arc additive manufacturing
2019 (English)In: Journal of laser applications, ISSN 1042-346X, E-ISSN 1938-1387, Vol. 31, no 2, article id 022307Article in journal (Refereed) Published
Abstract [en]

Additive manufacturing (AM) can be used for the fabrication of large metal parts, e.g., aerospace/space applications. Wire arc additivemanufacturing (WAAM) can be a suitable process for this due to its high deposition rates and relatively low equipment and operationcosts. In WAAM, an electrical arc is used as a heat source and the material is supplied in the form of a metal wire. A known disadvantageof the process is the comparably low dimensional accuracy. This is usually compensated by generating larger structures than desired andmachining away excess materials. So far, using combinations of arc in atmospheric conditions with high precision laser heat sources forAM has not yet been widely researched. Properties of the comparable cheap arc-based process, such as melt pool stability and dimensionalaccuracy, can be improved with the addition of a laser source. Within this paper, impacts of adding a laser beam to the WAAMprocess are presented. Differences between having the beam in a leading or a trailing position, relative to the wire and arc, are alsorevealed. Structures generated using the arc-laser-hybrid processes are compared to ones made using only an arc as the heat source. Bothgeometrical and material aspects are studied to determine the influences of laser hybridization, applied techniques including x ray,energy-dispersive X-ray spectroscopy, and high precision 3D scanning. A trailing laser beam is found to best improve topological capabilitiesof WAAM. Having a leading laser beam, on the other hand, is shown to affect cold metal transfer synergy behavior, promotinghigher deposition rates but decreasing topological accuracy.

Place, publisher, year, edition, pages
American Institute of Physics (AIP), 2019
Keywords
additive manufacturing, laser augmentation, gas metal arc, hybrid processing, wire arc additive manufacturing/WAAM
National Category
Manufacturing, Surface and Joining Technology
Research subject
Manufacturing Systems Engineering
Identifiers
urn:nbn:se:ltu:diva-74233 (URN)10.2351/1.5096111 (DOI)
Conference
Proceedings of the International Congress of Applications of Lasers & Electro-Optics (ICALEO® 2018)
Funder
Interreg Nord, 20200060
Note

Konferensartikel i tidskrift

Available from: 2019-06-07 Created: 2019-06-07 Last updated: 2019-06-25Bibliographically approved
Näsström, J., Brueckner, F. & Kaplan, A. (2019). Measuring the effects of a laser beam on melt pool fluctuation in arc additive manufacturing. Rapid prototyping journal, 25(3), 488-495
Open this publication in new window or tab >>Measuring the effects of a laser beam on melt pool fluctuation in arc additive manufacturing
2019 (English)In: Rapid prototyping journal, ISSN 1355-2546, E-ISSN 1758-7670, Vol. 25, no 3, p. 488-495Article in journal (Refereed) Published
Abstract [en]

Purpose

The steadily growing popularity of additive manufacturing (AM) increases the demand for understanding fundamental behaviors of these processes. High-speed imaging (HSI) can be a useful tool to observe these behaviors, but many studies only present qualitative analysis. The purpose of this paper is to propose an algorithm-assisted method as an intermediate to rapidly quantify data from HSI. Here, the method is used to study melt pool surface profile movement in a cold metal transfer-based (CMT-based) AM process, and how it changes when the process is augmented with a laser beam.

Design/methodology/approach

Single-track wide walls are generated in multiple layers using only CMT, CMT with leading and with trailing laser beam while observing the processes using HSI. The studied features are manually traced in multiple HSI frames. Algorithms are then used for sorting measurement points and generating feature curves for easier comparison.

Findings

Using this method, it is found that the fluctuation of the melt surface in the chosen CMT AM process can be reduced by more than 35 per cent with the addition of a laser beam trailing behind the arc. This indicates that arc and laser can be a viable combination for AM.

Originality/value

The suggested quantification method was used successfully for the laser-arc hybrid process and can also be applied for studies of many other AM processes where HSI is implemented. This can help fortify and expand the understanding of many phenomena in AM that were previously too difficult to measure.

Place, publisher, year, edition, pages
Emerald Group Publishing Limited, 2019
Keywords
Melt flow, Cold metal transfer, High speed imaging, Material deposition, Quantifying results
National Category
Manufacturing, Surface and Joining Technology
Research subject
Manufacturing Systems Engineering
Identifiers
urn:nbn:se:ltu:diva-71688 (URN)10.1108/RPJ-01-2018-0033 (DOI)000464998000006 ()
Note

Validerad;2019;Nivå 2;2019-04-23 (oliekm)

Available from: 2018-11-21 Created: 2018-11-21 Last updated: 2019-06-14Bibliographically approved
Siva Prasad, H., Brueckner, F. & Kaplan, A. (2019). Powder catchment in laser metal deposition. Paper presented at 37th International Congress of Applications of Lasers & Electro-Optics (ICALEO 2018). 14-18 October 2018, Orlando, Florida. Journal of laser applications, 31(2), Article ID 022308.
Open this publication in new window or tab >>Powder catchment in laser metal deposition
2019 (English)In: Journal of laser applications, ISSN 1042-346X, E-ISSN 1938-1387, Vol. 31, no 2, article id 022308Article in journal (Refereed) Published
Abstract [en]

Laser metal deposition (LMD) of Inconel 718 using a coaxial nozzle is investigated by high-speed imaging. The interaction of individualpowder grains with the laser induced melt pool surface and, finally, their catchment in the LMD track is observed. Powder catchment trendsare explained by interpreting physical phenomena, such as the melt flow and surface tension. Distinct zones for powder catchment are categorizeddepending on the position of initial interaction between powder grains and the melt pool. Particles are introduced outside the meltpool ricochet and do not attach to the clad. Particles arriving outside the laser spot, onto the solidifying skin of the melt pool, are caught,and may incorporate. Some particles may remain on the clad surface as surface roughness on the built part. Particles interacting with thelaser-irradiated region of the melt pool tend to move toward its center and readily incorporate into the melt. Quantitative analyses of highspeedvideos are carried out to measure incorporation time of powder grains in the melt pool, their velocity, and distance traveled.

Place, publisher, year, edition, pages
American Institute of Physics (AIP), 2019
Keywords
laser metal deposition, additive manufacturing, high-speed imaging, powder catchment mechanisms, blown powder, laser cladding
National Category
Manufacturing, Surface and Joining Technology
Research subject
Manufacturing Systems Engineering
Identifiers
urn:nbn:se:ltu:diva-73750 (URN)10.2351/1.5096130 (DOI)2-s2.0-85064609365 (Scopus ID)
Conference
37th International Congress of Applications of Lasers & Electro-Optics (ICALEO 2018). 14-18 October 2018, Orlando, Florida
Note

Konferensartikel i tidskrift

Available from: 2019-04-24 Created: 2019-04-24 Last updated: 2019-05-15Bibliographically approved
Robertson, S., Frostevarg, J., Kaplan, A., Hong, S. M., Kim, J.-H. & Bang, H.-S. (2019). Tailored laser pulse method to manipulate filler wire melt metallurgy from thermal cycles. Paper presented at Proceedings of the International Congress of Applications of Lasers & Electro-Optics (ICALEO® 2018).. Journal of laser applications, 31(2), Article ID 022605.
Open this publication in new window or tab >>Tailored laser pulse method to manipulate filler wire melt metallurgy from thermal cycles
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2019 (English)In: Journal of laser applications, ISSN 1042-346X, E-ISSN 1938-1387, Vol. 31, no 2, article id 022605Article in journal (Refereed) Published
Abstract [en]

A robust method is introduced to simulate and study the filler wire metallurgy for controlled cooling conditions after melting, enabling efficient mapping with prompt analysis of trends. Proposed is a reduced, though representative, process with more controllable conditions. Short lengths of filler wires are preplaced in a cavity, drilled into a base metal sheet. Irradiation by a pulsed laser beam melts the wire to generate a sample nugget. Pulse shaping influences the cooling rate, granting the ability to tailor weldament microstructures. The method is demonstrated for S1100QL steel and undermatched filler wire, to obtain high toughness for processes like laser-arc hybrid welding, where a representative thermal cycle is needed. For high toughness, a controlled amount of acicular ferrite and, in turn, nonmetallic inclusions is desirable. This “snapshot” method has revealed a characteristic histogram of inclusion sizes, for different pulse shapes. Additional information on the thermal cycle can be acquired by employing thermocouples, a pyrometer, or advanced methods like high speed imaging or modeling. The method offers a wide spectrum of variants and applications.

Place, publisher, year, edition, pages
USA: Laser Institute of America, 2019
National Category
Manufacturing, Surface and Joining Technology
Research subject
Manufacturing Systems Engineering
Identifiers
urn:nbn:se:ltu:diva-75401 (URN)10.2351/1.5096145 (DOI)2-s2.0-85065039863 (Scopus ID)
Conference
Proceedings of the International Congress of Applications of Lasers & Electro-Optics (ICALEO® 2018).
Projects
OptoSteel
Note

Konferensartikel i tidskrift

Available from: 2019-08-06 Created: 2019-08-06 Last updated: 2019-08-13Bibliographically approved
Siva Prasad, H., Frostevarg, J. & Kaplan, A. (2019). The stability of laser welding with an off-axis wire feed. Journal of Materials Processing Technology, 264, 84-90
Open this publication in new window or tab >>The stability of laser welding with an off-axis wire feed
2019 (English)In: Journal of Materials Processing Technology, ISSN 0924-0136, E-ISSN 1873-4774, Vol. 264, p. 84-90Article in journal (Refereed) Published
Abstract [en]

The concept using an off-axis filler wire during laser welding is introduced here in order to provide added process robustness considering gap width variations. Its stability is investigated with respect to gap width, welding speeds and powers. Geometry of the welds is analysed by tracing of weld cap edges and joint cross sections, connecting trends to weld parameters. High speed imaging and streak images are used to further study and describe sequences of events, including undercut formation. Formation of imperfections are found to be mainly correlated to wire feed position variations at the surface due to irregular melting of the wire tip.

Place, publisher, year, edition, pages
Elsevier, 2019
National Category
Manufacturing, Surface and Joining Technology
Research subject
Manufacturing Systems Engineering
Identifiers
urn:nbn:se:ltu:diva-70826 (URN)10.1016/j.jmatprotec.2018.09.003 (DOI)000450135400009 ()2-s2.0-85053062410 (Scopus ID)
Note

Validerad;2018;Nivå 2;2018-09-21 (svasva)

Available from: 2018-09-11 Created: 2018-09-11 Last updated: 2019-04-24Bibliographically approved
Volpp, J., Brueckner, F. & Kaplan, A. (2019). Track geometry variations in selective laser melting processes. Journal of laser applications, 31(2), Article ID 022310.
Open this publication in new window or tab >>Track geometry variations in selective laser melting processes
2019 (English)In: Journal of laser applications, ISSN 1042-346X, E-ISSN 1938-1387, Vol. 31, no 2, article id 022310Article in journal (Refereed) Published
Abstract [en]

Selective laser melting processes are widely used for many industrial applications using a laser beam to melt preplaced powder materiallayer by layer to create technical parts. The building process of those structures requires remelting of adjacent tracks and layers in order toavoid cavities and achieve the joining of the new track to the previous track and layer. In order to achieve a sufficient overlap and minimizecavities, usually conservative processing parameters are chosen. A higher energy and powder usage efficiency would be achieved if knowingabout the formation process of the single tracks and their geometrical dimensions depending on the available powder. In this work, it isshown that the cross-sectional track geometry significantly varies within one layer. A simple model is developed describing the influence ofthe available powder for each track within one layer. Depending on the hatch distance, different variation patterns are observed andmodeled showing that the track variations are inherent phenomena of the process. It can be concluded that the variations of powder avail-ability can cause the geometric variations of the tracks.

Place, publisher, year, edition, pages
American Institute of Physics (AIP), 2019
Keywords
laser additive manufacturing, selective laser melting, laser metal fusion, track geometry, powder availability
National Category
Manufacturing, Surface and Joining Technology
Research subject
Manufacturing Systems Engineering
Identifiers
urn:nbn:se:ltu:diva-73778 (URN)10.2351/1.5096107 (DOI)2-s2.0-85065612393 (Scopus ID)
Note

Validerad;2019;Nivå 2;2019-05-29 (oliekm)

Available from: 2019-04-29 Created: 2019-04-29 Last updated: 2019-08-19Bibliographically approved
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0002-3569-6795

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