oru.sePublications
Change search
Link to record
Permanent link

Direct link
BETA
Publications (10 of 16) Show all publications
Larsson, J., Jansson, A. & Karlsson, P. (2019). Monitoring and evaluation of the wire drawing process using thermal imaging. The International Journal of Advanced Manufacturing Technology, 101(5-8), 2121-2134
Open this publication in new window or tab >>Monitoring and evaluation of the wire drawing process using thermal imaging
2019 (English)In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 101, no 5-8, p. 2121-2134Article in journal (Refereed) Published
Abstract [en]

Wire drawing is a cold work metal forming process which is dependant of a functional lubrication process. If the lubrication fails, there is a risk that both the tools and the produced wire will be damaged. Process monitoring of wire drawing is rare in today’s industry since there are no commercialised methods that deliver consistent results. In this paper, a method for monitoring of the wire drawing process is proposed and evaluated. A thermal imaging camera was used for acquiring thermal images of the wire as it leaves the drawing tool. It was found that the proposed method could capture changes in the wire drawing process and had correlation to the drawing force. An equation for estimating the friction condition between the wire and the drawing die using the wire temperature was also proposed and evaluated against experiments. The results showed that the new equation produced results that correlated well to results obtained using a conventional equation that use drawing force.

Place, publisher, year, edition, pages
Springer, 2019
Keywords
Wire drawing, Thermal imaging camera, Process monitoring
National Category
Mechanical Engineering
Identifiers
urn:nbn:se:oru:diva-70616 (URN)10.1007/s00170-018-3021-7 (DOI)000463240400076 ()2-s2.0-85057885212 (Scopus ID)
Available from: 2018-12-10 Created: 2018-12-10 Last updated: 2019-06-18Bibliographically approved
Larsson, J., Karlsson, P. & Pejryd, L. (2019). The effect of bearing length on the surface quality of drawn wire. In: : . Paper presented at 89th Annual Convention of the Wire Association International, Atlanta, USA, May 13-16, 2019.
Open this publication in new window or tab >>The effect of bearing length on the surface quality of drawn wire
2019 (English)Conference paper, Published paper (Refereed)
Abstract [en]

In wire drawing, the geometry of drawing dies influences the performance of the wire process. This study investigates the effect of bearing lengths on the surface quality of the drawn wire. Wire drawing tests were done using an industrial wiredrawing machine utilizing drawing dies with different bearing lengths. The influence of bearing length on surface quality is discussed.

Keywords
Wire, Bearing length, Wire drawing
National Category
Mechanical Engineering Tribology (Interacting Surfaces including Friction, Lubrication and Wear)
Research subject
Mechanical Engineering
Identifiers
urn:nbn:se:oru:diva-75164 (URN)
Conference
89th Annual Convention of the Wire Association International, Atlanta, USA, May 13-16, 2019
Available from: 2019-07-19 Created: 2019-07-19 Last updated: 2019-07-25Bibliographically approved
Surreddi, K. B., Oikonomou, C., Karlsson, P., Olsson, M. & Pejryd, L. (2018). In-situ micro-tensile testing of additive manufactured maraging steels in the SEM: Influence of build orientation, thickness and roughness on the resulting mechanical properties. La Metallurgia Italiana (3), 27-33
Open this publication in new window or tab >>In-situ micro-tensile testing of additive manufactured maraging steels in the SEM: Influence of build orientation, thickness and roughness on the resulting mechanical properties
Show others...
2018 (English)In: La Metallurgia Italiana, ISSN 0026-0843, no 3, p. 27-33Article in journal (Refereed) Published
Abstract [en]

Selective laser melting (SLM) is frequently used additive manufacturing technique capable of producing various complex parts including thin-wall sections. However the surface roughness is a limiting factor in thin sections produced by SLM process when strength is the main criterion. In this study, the influence of build orientation, thickness and roughness on the resulting mechanical properties of as-built test samples was investigated. Various thin sheets of EN 1.2709 maraging steel built in horizontal and vertical orientations produced by SLM were investigated using in-situ micro-tensile testing in a scanning electron microscope. The mechanical strength and deformation mechanisms were analyzed and explained based on thickness and build orientation. Increased ductility was observed in thicker samples as well as in the horizontal build samples. The results illustrate the potential of the in-situ test technique and aspects important to consider in design guidelines for thin AM structures.

Place, publisher, year, edition, pages
Associazione Italiana di Metallurgia, 2018
Keywords
selective laser melting, in-situ micro-tensile testing, build orientation, deformation mechanism and maraging steel
National Category
Metallurgy and Metallic Materials
Identifiers
urn:nbn:se:oru:diva-68092 (URN)000435488500005 ()
Projects
ATOAM
Funder
Knowledge Foundation
Available from: 2018-07-24 Created: 2018-07-24 Last updated: 2018-07-31Bibliographically approved
Karlsson, P., Pejryd, L. & Oikonomou, C. (2017). Factors Influencing Mechanical Properties of Additive Manufactured Thin-Walled Parts. In: Euro PM2017 Congress Proceedings: . Paper presented at Euro PM2017 Congress & Exhibition, Milan, Italy, October 1-5, 2017. European Powder Metallurgy Association (EPMA)
Open this publication in new window or tab >>Factors Influencing Mechanical Properties of Additive Manufactured Thin-Walled Parts
2017 (English)In: Euro PM2017 Congress Proceedings, European Powder Metallurgy Association (EPMA) , 2017Conference paper, Published paper (Refereed)
Abstract [en]

By using the Additive Manufacturing (AM) method it is possible to manufacture components with thin-walled sections and complex geometry. However, it is not clear when the surface becomes the strength limiting factor on thin-walled sections in the components or if the thickness of the components is reduced. Also, the microstructure of AM produced specimens may be heterogeneous and it is not clear how the build direction influence the strength of thin section components. In the present study, the influence of component thickness, surface roughness and build direction on the strength of AM produced components were investigated. Test specimens were manufactured using EOS M290 3D-printer and EN 1.2709 maraging steel powder. To investigate when the part thickness, surface and built orientation becomes the strength limiting factors tensile testing using thin samples built in both  horizontal and vertical build orientation with thicknesses ranging from 0.2 mm to 4 mm was performed. Results on strength limiting factors are discussed.

Place, publisher, year, edition, pages
European Powder Metallurgy Association (EPMA), 2017
Keywords
additive manufacturing, material strength, thin-walled AM structures, steel
National Category
Mechanical Engineering Materials Engineering
Research subject
Mechanical Engineering
Identifiers
urn:nbn:se:oru:diva-61212 (URN)
Conference
Euro PM2017 Congress & Exhibition, Milan, Italy, October 1-5, 2017
Available from: 2017-10-02 Created: 2017-10-02 Last updated: 2019-03-29Bibliographically approved
Pejryd, L., Karlsson, P., Hällgren, S. & Kahlin, M. (2016). Non-destructive evaluation of internal defects in additive manufactured aluminium. In: : . Paper presented at World PM 2016, Powder Metallurgy World Congress, Hamburg, Germany, October 9-13, 2016.
Open this publication in new window or tab >>Non-destructive evaluation of internal defects in additive manufactured aluminium
2016 (English)Conference paper, Published paper (Refereed)
Keywords
additive manufacturing, selective laser melting, aluminium, computed tomography, ultrasonic inspection, eddy current
National Category
Mechanical Engineering Materials Engineering
Research subject
Mechanical Engineering
Identifiers
urn:nbn:se:oru:diva-51003 (URN)
Conference
World PM 2016, Powder Metallurgy World Congress, Hamburg, Germany, October 9-13, 2016
Available from: 2016-06-21 Created: 2016-06-21 Last updated: 2017-12-05Bibliographically approved
Gåård, A., Karlsson, P., Krakhmalev, P. & Broitman, E. (2015). Nano-scale friction of multi-phase powder metallurgy tool steels. Advanced Materials Research, 1119, 70-74
Open this publication in new window or tab >>Nano-scale friction of multi-phase powder metallurgy tool steels
2015 (English)In: Advanced Materials Research, ISSN 1022-6680, E-ISSN 1662-8985, Vol. 1119, p. 70-74Article in journal (Refereed) Published
Abstract [en]

Friction is a fundamental phenomenon in tribology involving complex mechanisms between thecontacting surfaces. Measurements of friction are often made using devices with substantially largercontact area than dimensions corresponding to microstructural features of the materials. Hence, for multi-phase materials,influence of particular microstructural constituents is not resolved. In the present work, a tribometerwith a contact area in the nano-scale range was used to map friction for different types of tool steelswith different chemical- and phase composition. Owing to the small tip radius, frictionalcharacteristics of primary carbides and the steel matrix were measured and compared. Dependingon chemical composition, a difference was observed where the coefficient of friction wasapproximately twice higher for the steel possessing highest coefficient of friction, including bothcarbides and the steel matrix.

Place, publisher, year, edition, pages
Trans Tech Publications, 2015
Keywords
friction, microstructure, tool steel
National Category
Tribology (Interacting Surfaces including Friction, Lubrication and Wear) Mechanical Engineering Materials Engineering
Research subject
Mechanical Engineering; Physics
Identifiers
urn:nbn:se:oru:diva-58837 (URN)10.4028/www.scientific.net/AMR.1119.70 (DOI)
Available from: 2017-07-24 Created: 2017-07-24 Last updated: 2018-07-09Bibliographically approved
Karlsson, P., Gåård, A., Krakhmalev, P. & Berhe-Larsson, J. (2014). Influence of tool steel hard phase orientation and shape on galling. Advanced Materials Research, 966-96, 249-258
Open this publication in new window or tab >>Influence of tool steel hard phase orientation and shape on galling
2014 (English)In: Advanced Materials Research, ISSN 1022-6680, E-ISSN 1662-8985, Vol. 966-96, p. 249-258Article in journal (Refereed) Published
Abstract [en]

Conventionally manufactured cold work tool steel is often used in sheet metal forming as die material. Due to the forging process, the as-cast network structure of carbides is broken into elongated particles. Depending on the tool cross-section, the orientation and shape of carbides in the active tool surface is different. In the present research, the influence of tool steel hard phase orientation and shape on galling was investigated. D2 type tool steel was cut in three different orientations and tested in lubricated sliding conditions against AISI 304 austenitic stainless steel. Tests were performed using a Slider-On-Flat-Surface and galling was detected by changes in friction and post-test microscopy. The lubricant was Castrol FST8 using 5 g/m2 sheet material. Results showed a strong correlation between sliding distance to galling and tool steel hard phase orientation and shape at low loads, whereas high load contact resulted in early galling in all cases. Material transfer was observed mainly to the tool steel matrix. The worst performance was observed for specimens cut so that the tool steel hard phase, M7C3 carbides in the D2 steel, were oriented along the sliding direction, which resulted in longer open tool matrix areas contacting the sheet material.

Place, publisher, year, edition, pages
Trans Tech Publications, 2014
Keywords
Austenitic stainless steel; Carbides; Industrial engineering; Joining; Lubricants; Plastic deformation; Production engineering; Sheet metal; Tribology; Wear of materials, Cold work tool steels; Elongated particles; Galling; Material transfers; Metal transfers; Network structures; Sliding conditions; Strong correlation, Tool steel
National Category
Tribology (Interacting Surfaces including Friction, Lubrication and Wear) Mechanical Engineering Materials Engineering
Research subject
Mechanical Engineering
Identifiers
urn:nbn:se:oru:diva-58820 (URN)10.4028/www.scientific.net/AMR.966-967.249 (DOI)2-s2.0-84904014001 (Scopus ID)
Available from: 2014-05-19 Created: 2017-07-24 Last updated: 2019-03-05Bibliographically approved
Karlsson, P., Gåård, A. & Krakhmalev, P. (2014). Influence of tool steel microstructure on friction and initial material transfer. Wear, 319(1-2), 12-18
Open this publication in new window or tab >>Influence of tool steel microstructure on friction and initial material transfer
2014 (English)In: Wear, ISSN 0043-1648, E-ISSN 1873-2577, Vol. 319, no 1-2, p. 12-18Article in journal (Refereed) Published
Abstract [en]

An investigation was conducted to study the influence of tool steel microstructure on initial material transfer and friction. Two different powder metallurgy tool steels and an ingot cast tool material were tested in dry sliding against 1.4301, 1.4162, Domex 355 MC and Domex 700 MC sheet materials. It was found that tool steel hard phase heights influence initial material transfer and friction. The coefficient of friction increased with decreasing tool steel hard phase heights at 50 N normal load and initial material transfer occurred around protruding hard phases. At higher load of 500 N the sheet material adhered to both the tool steel matrix and hard phases. Coefficient of friction decreased with increasing proof strength of the sheet material at 500 N normal load.

Place, publisher, year, edition, pages
Elsevier, 2014
Keywords
Material transfer, Friction, Galling, Microstructure, Tool steel
National Category
Tribology (Interacting Surfaces including Friction, Lubrication and Wear) Mechanical Engineering Materials Engineering
Research subject
Materials Engineering; Mechanical Engineering
Identifiers
urn:nbn:se:oru:diva-58816 (URN)10.1016/j.wear.2014.07.002 (DOI)000345061600002 ()2-s2.0-84905374924 (Scopus ID)
Available from: 2014-05-19 Created: 2017-07-24 Last updated: 2018-01-13Bibliographically approved
Karlsson, P. (2014). The influence of tool steel microstructure on galling. (Doctoral dissertation). Karlstad: Karlstads universitet
Open this publication in new window or tab >>The influence of tool steel microstructure on galling
2014 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

In sheet metal forming (SMF) of materials such as stainless steels there is a major problem with transfer and accumulation of sheet material to the metal forming tool surface. The problem is known as galling; a sort of severe adhesive wear, which results in severe scratching of produced parts. In this thesis, the overall aim was to gain knowledge of the influence of tool steel microstructure on galling initiation under sliding conditions. It was discovered that material transfer and tool steel damage caused by sheet material flow creating wear-induced galling initiation sites occurred in the early stage of galling. The galling resistance was higher for tool steels with higher matrix hardness due to better resistance to tool steel damage. Initial friction and critical contact pressure to galling was influenced by the strength of the sheet material. Material transfer happened at low pressures and the friction value was high in a case of sheet materials with lower proof strength, possibly due to the sheet contact against the tool steel matrix resulting in high adhesion and quicker tool damage. It was demonstrated that, in addition to hardness of the tool steel matrix and sheet material proof strength, tool steel microstructural features like size, shape, distribution and height of hard phases are important parameters influencing galling. Tool steels comprising homogeneously distributed, small and high hard phases better prevented the contact between sheet material and the tool steel matrix. Thus, a metal to metal contact with high friction was more efficiently avoided, which resulted in better tool performance.

 

Place, publisher, year, edition, pages
Karlstad: Karlstads universitet, 2014. p. 42
Series
Karlstad University Studies, ISSN 1403-8099 ; 2014:35
Keywords
Galling, Microstructure, Material transfer, Tool steel, Stainless steel, Metall transfer
National Category
Tribology (Interacting Surfaces including Friction, Lubrication and Wear) Materials Engineering Mechanical Engineering
Research subject
Materials Engineering
Identifiers
urn:nbn:se:oru:diva-61013 (URN)978-91-7063-568-7 (ISBN)
Public defence
2014-08-29, Ljungbergsalen, 21A 244, Universitetsgatan 2, 10:15 (English)
Opponent
Supervisors
Available from: 2017-09-21 Created: 2017-09-14 Last updated: 2018-06-25Bibliographically approved
Karlsson, P., Krakhmalev, P., Gåård, A. & Bergström, J. (2013). Influence of work material proof stress and tool steel microstructure on galling initiation and critical contact pressure. Tribology International, 60, 104-110
Open this publication in new window or tab >>Influence of work material proof stress and tool steel microstructure on galling initiation and critical contact pressure
2013 (English)In: Tribology International, ISSN 0301-679X, E-ISSN 1879-2464, Vol. 60, p. 104-110Article in journal (Refereed) Published
Abstract [en]

EN 1.4301 (austenitic), EN 1.4509 (ferritic), EN 1.4162 (duplex) and EN 1.4310 C1000 (metastable austenitic) stainless steels were tested in lubricated sliding against an ingot cast EN X153WCrMoV12 and powder metallurgy nitrogen alloyed Uddeholm Vancron 40 tool steels to reveal critical to galling contact pressure, Pcr. The calculated Pcr were higher for steels with higher strength. At P>Pcr, due to plastic flow of sheet material, the tool is damaged substantially and wear-induced matrix damage causes rapid galling initiation. At P<Pcr, galling was not observed. The powder metallurgy tool steel was more resistant to galling against all tested stainless steels. Better performance was associated with fine and homogeneously distributed hard phases preventing intensive wear of the tool steel matrix.

Place, publisher, year, edition, pages
Elsevier, 2013
Keywords
Galling, Tool steels, Stainless steel, Wear
National Category
Tribology (Interacting Surfaces including Friction, Lubrication and Wear) Mechanical Engineering Materials Engineering
Research subject
Materials Engineering; Mechanical Engineering
Identifiers
urn:nbn:se:oru:diva-58821 (URN)10.1016/j.triboint.2012.10.023 (DOI)000315550700014 ()2-s2.0-84870371161 (Scopus ID)
Available from: 2012-10-26 Created: 2017-07-24 Last updated: 2018-01-13Bibliographically approved
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0002-8144-8821

Search in DiVA

Show all publications