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  • 1.
    Asnafi, Nader
    Örebro University, School of Science and Technology.
    3D Metal Printing from an Industrial Perspective: Product Design, Production and Business Models2018Conference paper (Refereed)
    Abstract [en]

    This paper summarizes the current position of 3D metal printing/additive manufacturing (henceforth called 3D metal printing) from an industrial perspective. The new possibilities to design the part differently simply because the new shape can be produced and which provides benefits with respect to improved material utilization degree, reduced weight, size etc. are addressed in this paper. Different types of generative design concepts such as form synthesis, topology optimization and lattice and surface optimization are exemplified. Low volume production by 3D metal printing is discussed. High volume production by 3D metal printing of manufacturing tools and dies is described.

    Tool & die production is an important phase in the development of new components/product models. This phase determines both the lead time (Time-To-Production/-Market) and the size of the investments required to start the production. The lead time for the production of tools and dies for a new car body is currently about 12 months and needs to be reduced 40% by 2020. The lead time for injection molds for small and large series production must be reduced to 10 days and 4 weeks respectively. Lead time and cost-efficient metallic tools can be provided by 3D metal printing. This paper focuses on tools and dies for the manufacture of sheet metal & plastic components for the engineering, automotive and furniture industries. The paper includes Powder Bed Fusion (PBF). Digitalization through virtual tool & die design and optimization of the tool & die production combined with the PBF´s digital essence provides greater flexibility, better efficiency, tremendous speed, improved sustainability and increased global competitiveness.

    3D metal printing is expected to result in several changes in the supplier chain and generate new business models. The present paper describes some of the changes 3D metal printing has led to and is expected to result in within the engineering and automotive industry in Europe during the coming years.

  • 2.
    Asnafi, Nader
    Örebro University, School of Science and Technology.
    3D Metal Printing from an Industrial Perspective: Product Examples, Production and Business Models2018Conference paper (Refereed)
    Abstract [en]

    This paper summarizes the current position of 3D metal printing/additive manufacturing (henceforth called 3D metal printing) by the so-called Powder Bed Fusion (PBF) from an industrial perspective, particularly in Sweden.

    The new possibilities to design the part differently simply because the new shape can be produced and which provides benefits with respect to improved material utilization degree, reduced weight, size etc. are addressed in this paper.

    Tool & die production is an important phase in the development of new components/product models. This phase determines both the lead time (Time-To-Production/‐Market) and the size of the investments required to start the production. The lead time for the production of tools and dies for a new car body is currently about 12 months and needs to be reduced 40% by 2020. The lead time for injection molds for small and large series production must be reduced to 10 days and 4 weeks respectively. Lead time and cost-efficient metallic tools can be provided by 3D metal printing. This paper focuses on tools and dies for the manufacture of sheet metal & plastic components for the engineering and automotive industries.

    Digitalization through virtual tool & die design and optimization of the tool & die production combined with the PBF´s digital essence provides greater flexibility, better efficiency, tremendous speed, improved sustainability and increased global competitiveness.

    3D metal printing is expected to result in several changes in the supplier chain and generate new business models. The present paper describes some of the changes 3D metal printing has led to and is expected to result in within the engineering and automotive industry during the coming years.

  • 3.
    Asnafi, Nader
    Örebro University, School of Science and Technology.
    3D Metal Printing of Industrial Tools & Dies2019Conference paper (Other academic)
    Abstract [en]

    Tool & die production is an important phase in the development of new components/product models. This phase determines both the lead time (Time-To-Production/-Market) and the size of the investments required to start the production. This paper is focused on Powder Bed Fusion (PBF) and summarizes the current position of 3D metal printing/additive manufacturing (henceforth called 3D metal printing)of industrial tools & dies. It also exhibits the new possibilities to design the tool/die differently simply because the new shape can be produced. Different types of generative design concepts such as form synthesis, topology optimization and lattice and surface optimization are exemplified. The paper exemplifies business cases, the shorter lead times, the associated improved material utilization degree, reduced weight,etc. Low volume production by 3D metal printing is discussed. High volume production by 3D metal printing of manufacturing tools and dies is described. The paper exhibits some examples of digitalization through virtual tool & die design and optimization of the tool& die production and how it provides greater flexibility, better efficiency, tremendous speed, improved sustainability and increased global competitiveness. 3D metal printing is expected to result in several changes in the supplier chain and generate new business models. The present paper describes some of the changes 3D metal printing has led to and is expected to result in within the engineering and automotive industry in Europe during the coming years.

  • 4.
    Asnafi, Nader
    Örebro University, School of Science and Technology.
    3D Metal Printing of Production Tools & Dies2018Conference paper (Refereed)
    Abstract [en]

    3D metal printing is of great interest for manufacturing of tools and dies for high volume production. It is possible to accomplish lead time reduction, tool and die weight saving, improved cycle time etc. The presentation deals primarily with Powder Bed Fusion as 3D printing method and describes 3D metal printing of tools & dies both scientifically and from an industrialization perspective. The presentation shows how far we have come in industrialization of 3D metal printing of tools & dies and what needs to be done to include 3D metal printing in the existing industrial systems and infrastructure.

  • 5.
    Asnafi, Nader
    Örebro University, School of Science and Technology.
    3D Printing / Additative Manufacturing from Product Creator and Tool Maker Perspectives in the Automotive Industry2016Conference paper (Other academic)
  • 6.
    Asnafi, Nader
    VA Automotive AB, Hässleholm, Sweden .
    3D-printning från produktskapares och verktygsmakares perspektiv2015Conference paper (Other academic)
  • 7.
    Asnafi, Nader
    Örebro University, School of Science and Technology.
    3rd International Conference on Material Engineering and Advanced Manufacturing Technology, 26–28 April 2019, Shanghai, China2020Conference proceedings (editor) (Refereed)
    Abstract [en]

    We are very pleased to present the proceedings of the 3rd International Conference on Material Engineering and Advanced Manufacturing Technology (MEAMT 2019) that was held successfully under the auspices of IASED in Shanghai, China, April 26-28, 2019.

    The theme of the conference - Material Engineering and Advanced Manufacturing Technology - is of key importance to the science and technology and a sustainable industrial development. This conference promotes valuable contacts between academia and industry and addresses both basic research and the societal/industrial technological needs within Material Engineering and Advanced Manufacturing Technology.

    In this era of Industry 4.0, we hope that the conference provided applicable data/information, addressed the issues in the societal/industrial transformation, and facilitated exchange within and between academia and industry.

    We want to express our gratitude to the program chairs and all members of the advisory, publicity, and technical committees for their valuable time and advices. We are grateful to the world renowned scientists who acted as keynote speakers at the conference.

    After a rigorous review process, where each paper was reviewed by at least two reviewers, high quality papers were accepted for presentation at this conference. We would like to thank all the reviewers for their time, effort, and for completing their assignments on time albeit tight deadlines.

    Many thanks to the authors for their valuable contributions and to the attendees for their active participation.

    Finally, a big thank to the organizers who made this conference to yet another unforgettable experience.

    Nader Asnafi

    Professor of Mechanical Engineering, Örebro University, Sweden Editor of the proceedings of MEAMT 2019 One behalf of the conference committee.

  • 8.
    Asnafi, Nader
    Sapa Technology, Finspång (and Vetlanda), Sweden.
    Analytical modelling of the forces and pressures required in hydropiercing2000Report (Other academic)
  • 9.
    Asnafi, Nader
    Volvo Car Components Corporation/Industrial Development Centre, Olofström, Sweden.
    Analytical modelling of tube hydroforming1999In: Thin-walled structures, ISSN 0263-8231, E-ISSN 1879-3223, Vol. 34, no 4, p. 295-330Article in journal (Refereed)
    Abstract [en]

    The automotive industry has shown a growing interest in tube hydroforming during the past years. The advantages of hydroforming (less thinning, a more efficient manufacturing process etc.) can, for instance, be combined with the high strength of extra high strength steels, which are usually less formable, to produce structural automotive components which exhibit lower weight and improved service performance. Design and production of tubular components require knowledge about tube material behaviour and tribological effects during hydroforming and how the hydroforming operation itself should be controlled. These issues are studied analytically in the present paper. Hydroforming consists of free forming and calibration. Only the so-called free forming is treated here. The analytical models constructed in this paper are used to show what the limits are during the free forming, how different material and process parameters influence the loading path and the forming result, and what an experimental investigation into hydroforming should focus on. The present study was a part of a larger investigation, in which finite-element simulations and experiments were also conducted. The results of these simulations and experiments will be accounted for in coming papers.

  • 10.
    Asnafi, Nader
    Örebro University, School of Science and Technology.
    Application of Laser-based Powder Bed Fusion - Current Possibilities and Constraints for Tooling2021Conference paper (Refereed)
    Abstract [en]

    The current possibilities and constraints for tooling made by the application of Laser-based Powder Bed Fusion (L-PBF) is at the focus of this presentation. Design and manufacturing of production tools & dies for cold and hot working and injection molding are addressed. Solid and topology optimized tools are tested, compared with the conventionally designed and manufactured version of the same tools, and certified. The current possibilities and constraints are addressed from the material, technological and industrial perspectives. The current manufacturing readiness level and the industrialization status of metal additive manufacturing through L-PBF are evaluated.

  • 11.
    Asnafi, Nader
    Örebro University, School of Science and Technology.
    Application of Laser-Based Powder Bed Fusion for Direct Metal Tooling2021In: Metals, ISSN 2075-4701, Vol. 11, no 3, article id 458Article in journal (Refereed)
    Abstract [en]

    The journey of production tools in cold working, hot working, and injection molding from rapid tooling to additive manufacturing (AM) by laser-based powder bed fusion (L-PBF) is described. The current machines and their configurations, tool steel powder materials and their properties, and the L-PBF process parameters for these materials are specified. Examples of production tools designed for and made by L-PBF are described. Efficient design, i.e., high tooling efficiency and performance in operation, should be the primary target in tool design. Topology and lattice structure optimization provide additional benefits. Using efficient design, L-PBF exhibits the greatest potential for tooling in hot working and injection molding. L-PBF yields high tooling costs, but competitive total costs in hot working and injection molding. Larger object sizes that can be made by L-PBF, a larger number of powder metals that are designed for different tooling applications, lower feedstock and L-PBF processing costs, further L-PBF productivity improvement, improved surface roughness through L-PBF, and secured quality are some of the targets for the research and development in the future. A system view, e.g., plants with a high degree of automation and eventually with cyber-physically controlled smart L-PBF inclusive manufacturing systems, is also of great significance.

  • 12.
    Asnafi, Nader
    Volvo Car Corporation, Göteborg (and Olofström), Sweden.
    Automotive Tools & Dies - Volvo Cars Perspective2007Conference paper (Other academic)
  • 13.
    Asnafi, Nader
    Sapa Technology, Finspång (and Vetlanda), Sweden .
    Automotive Tubular Hydroforming: Fundmentals and Industrial Practice2000Conference paper (Other academic)
  • 14.
    Asnafi, Nader
    VA Automotive AB, Hässleholm, Sweden .
    Automotive/Car Body Stamping Tools & dies: 3D Printing Offers Shorter Lead Time and Reasonable Costs2016Conference paper (Other academic)
  • 15.
    Asnafi, Nader
    Örebro University, School of Science and Technology.
    Design and Additive Manufacturing of Tools for Forming and Trimming of up to 2-mm Thick DP6002020In: Current Trends in Sheet Metal Forming: Abstracts, 2020Conference paper (Refereed)
    Abstract [en]

    Design and manufacturing of stamping tools and dies are two important steps in the development of new components/products. These steps determine both the lead time (Time-To-Production/-Market) and the size of the investments required to start the production. 

    This paper deals with the design and production of stamping tools & dies for sheet metal components in up to 2-mm thick hot-dip galvanized DP600. Laser-based Powder Bed Fusion (LPBF) is the additive manufacturing (henceforth even called 3D printing) method used to make these tools and dies.

    The stamping tools & dies should withstand the requirements set in stamping of hot-dip galvanized DP600. Solid and topology optimized forming and cutting/blanking/trimming tools made in maraging steel (DIN 1.2709) by LPBF were subject to certification (approval/disapproval) for stamping of 2-mm thick hot-dip galvanized DP600. A working station in an industrial progressive die used for stamping of 1-mm thick DP600 was 3D-printed in DIN 1.2709, both with a honeycomb inner structure and after topology optimization, with successful results. 3D printing results in approved sheet metal parts, a significant lead time reduction and improved tool material efficiency. The 3D-printed tools and dies display acceptable wear behaviour. The cost for 3D-printed stamping tools and dies is, however, higher than the cost of those made conventionally. This cost increase can be accepted for the so-called late changes. This presentation is an account of the above-mentioned investigations.

    Download full text (pdf)
    Current Trends in Sheet Metal Forming. Abstracts
  • 16.
    Asnafi, Nader
    Jönköping University, Jönköping, Sweden .
    Development of Sustainable Products and Manufacturing/Production2014Conference paper (Other academic)
  • 17.
    Asnafi, Nader
    Örebro University, School of Science and Technology.
    Digitalization of the Swedish Industry2018Conference paper (Refereed)
  • 18.
    Asnafi, Nader
    Örebro University, School of Science and Technology.
    Digitalization of the Swedish Industry2018Conference paper (Refereed)
  • 19.
    Asnafi, Nader
    Örebro University, School of Science and Technology.
    Direct Rapid Tooling by Laser-based Powder Bed Fusion2021Conference paper (Refereed)
    Abstract [en]

    Additive manufacturing of production tools through laser-based powder bed fusion is at the focus of this presentation. Design and manufacturing of production tools & dies for stamping of sheet metal parts, cores (inserts) for injection moulding of plastic components and other types of production tools are addressed. Solid and topology optimized tools are tested, compared with the conventionally designed and manufactured version of the same tools, and certified. The current possibilities and constraints are addressed from the materials and technological perspectives. The current manufacturing readiness level and the industrialization status of metal additive manufacturing of tooling through laser-based powder bed fusion are evaluated.

  • 20.
    Asnafi, Nader
    Luleå University of Technology, Luleå, Sweden .
    Formbarhet under dragpressning, sträckpressning och bockning samt egenskaper efter formning av aluminiumplåt1988Report (Other academic)
  • 21.
    Asnafi, Nader
    Volvo Car Corporation, Göteborg (and Olofström), Sweden .
    Forming of Aluminium2002Conference paper (Other academic)
  • 22.
    Asnafi, Nader
    Swedish Institute for Metals Research, Stockholm, Sweden.
    Hydroformability of Extra High Strength Steels in Structural Tubular Applications: an Analysis based on Literature Survey1997Report (Other academic)
  • 23.
    Asnafi, Nader
    Örebro University, School of Science and Technology.
    Improved Lightweight Manufacturing Flexibility by Stamping of Selectively Laser Heat Treated Boron Steel Sheet2016Conference paper (Other academic)
  • 24.
    Asnafi, Nader
    Örebro University, School of Science and Technology.
    Innovative Lead Time and Cost Efficient Tools and Dies for Lightweight Autobody Components2016Conference paper (Other academic)
  • 25.
    Asnafi, Nader
    Uddeholms AB, Hagfors, Sweden .
    Kunddriven produktutveckling på en varierad marknad för global framgång2012Conference paper (Other academic)
  • 26.
    Asnafi, Nader
    Volvo Car Corporation, Göteborg (and Olofström), Sweden .
    Manufacturing the car body of tomorrow2002Conference paper (Other academic)
  • 27.
    Asnafi, Nader
    Örebro University, School of Science and Technology.
    Metal Additive Manufacturing – State of the Art 2020: A special issue of Metals2021Collection (editor) (Refereed)
    Abstract [en]

    Additive manufacturing (AM), more popularly known as 3D printing, comprises a group of technologies used to produce objects through the addition (rather than removal) of material. AM is used in many industries—aerospace and defense, automotive, consumer products, industrial products, medical devices, and architecture. AM is transforming the industry, and this industrial transformation is expected to become more comprehensive and reach a higher pace during the coming years.

    Additive manufacturing of metal components with virtually no geometric limitations has enabled new product design options and opportunities, increased product performance, shorter cycle time in part production, total cost reduction, shortened lead time, improved material efficiency, more sustainable products and processes, full circularity in the economy, and new revenue streams.

    This Special Issue of Metals focuses on metal additive manufacturing with respect to the topics mentioned below (please see the Keywords/Topics below). The papers presented in this Special Issue give an account of the 2020 scientific, technological, and industrial state of the art for metal additive manufacturing from different perspectives (see the Keywords/Topics below). Your contribution to this 2020 account is highly valuable and appreciated. 

    The submitted contribution should address metal additive manufacturing with respect to one or several of the following topics:

    • Business models and engineering
    • Product/component design (including generative design, topology optimization, lattice and surface optimization, etc.)
    • Industrial applications (aerospace, defense, automotive, consumer, medical, and industrial products, etc.)
    • Material and process design and engineering
    • New materials
    • Powder production and characterization
    • Systems and equipment engineering
    • Post-processing
    • Process control and optimization and quality assurance

  • 28.
    Asnafi, Nader
    Örebro University, School of Science and Technology.
    Metal Additive Manufacturing of Production Tools through Laser-based Powder Bed Fusion - Current Possibilities and Constraints2021Conference paper (Refereed)
    Abstract [en]

    Invited keynote speech

    Additive manufacturing of production tools through laser-based powder bed fusion is at the focus of this keynote presentation. Design and manufacturing of production tools & dies for stamping of sheet metal parts, cores (inserts) for injection moulding of plastic components, and other types of production tools are addressed. Solid and topology optimized tools are tested, compared with the conventionally designed and manufactured version of the same tools, and certified. The current possibilities and constraints are addressed from the material, technological and business perspectives. The current manufacturing readiness level and the industrialization status of metal additive manufacturing through laser-based powder bed fusion are evaluated.

  • 29.
    Asnafi, Nader
    Örebro University, School of Science and Technology.
    Metal Additive Manufacturing of Production Tools through Laser-based Powder Bed Fusion - Current Possibilities and Constraints2020Conference paper (Refereed)
    Abstract [en]

    Additive manufacturing of production tools through laser-based powder bed fusion is at the focus of this presentation. Design and manufacturing of production tools & dies for stamping of sheet metal parts, cores (inserts) for injection moulding of plastic components and other types of production tools are addressed. Solid and topology optimized tools are tested, compared with the conventionally designed and manufactured version of the same tools, and certified. The current possibilities and constraints are addressed from the material, technological and business perspectives. The current manufacturing readiness level and the industrialization status of metal additive manufacturing through laser-based powder bed fusion are evaluated.

  • 30.
    Asnafi, Nader
    Örebro University, School of Science and Technology.
    Metal Additive Manufacturing/3D Metal Printing in the Circular Economy2018Conference paper (Refereed)
  • 31.
    Asnafi, Nader
    Örebro University, School of Science and Technology.
    Metal Additive Manufacturing—State of the Art 20202021In: Metals, ISSN 2075-4701, Vol. 11, no 6, article id 867Article in journal (Refereed)
    Download full text (pdf)
    Metal Additive Manufacturing—State of the Art 2020
  • 32.
    Asnafi, Nader
    Volvo Car Corporation, Göteborg (and Olofström), Sweden .
    Nya material och processer vid framtagning av lättviktskarosser2004Conference paper (Other academic)
  • 33.
    Asnafi, Nader
    Swedish Institute for Metals Research, Stockholm, Sweden .
    On Prediction of the Yield Strength of Pressed Panels by Using the Tensile Behaviour of the Virgin Material1992Conference paper (Other academic)
  • 34.
    Asnafi, Nader
    Gränges Technology, Finspång, Sweden.
    On springback of double-curved autobody panels2001In: International Journal of Mechanical Sciences, ISSN 0020-7403, E-ISSN 1879-2162, Vol. 43, no 1, p. 5-37Article in journal (Refereed)
    Abstract [en]

    The springback of double curved autobody panels is studied theoretically and experimentally. Both steel and aluminum sheets are included in this investigation. The obtained results show that the springback is decreased with increasing binder force, increasing curvature, increasing sheet thickness and decreasing yield strength. This paper comprises also a discussion on the plastic strains and their influence on the springback.

  • 35.
    Asnafi, Nader
    Industrial Development Center/Volvo Cars Body Components, Olofström, Sweden .
    On Springback of Double-Curved Autobody Panels1998In: Proceedings, working groups meeting - IDDRG, International Deep Drawing Research Group: Genval, Benelux, June 15 - 16, 1998, 1998Conference paper (Other academic)
  • 36.
    Asnafi, Nader
    Swedish Institute for Metals Research, Stockholm, Sweden.
    On Springback of Double-Curved Autobody Panels, Part I: Theoretical Treatment1996Report (Other academic)
  • 37.
    Asnafi, Nader
    Swedish Institute for Metals Research, Stockholm, Sweden.
    On Springback of Double-Curved Autobody Panels, Part II: Experimental Analysis1996Report (Other academic)
  • 38.
    Asnafi, Nader
    Swedish Institute for Metals Research, Stockholm, Sweden .
    On strength, stiffness and dent resistance of car body panels1995In: Journal of Materials Processing Technology, ISSN 0924-0136, E-ISSN 1873-4774, Vol. 49, no 1-2, p. 13-31Article in journal (Refereed)
    Abstract [en]

    There are cases in which practitioners wish to be able to predict the properties of a panel, should they replace one material by another. In this study, the yield strength, stiffness and dent resistance of double-curvature car body panels are treated both theoretically and experimentally. The results of the investigation show that the above-mentioned properties of a pressed panel can be predicted provided that the magnitude of the principal surface strains and the magnitude of the panel radii at the panel centre are known.

  • 39.
    Asnafi, Nader
    Swedish Institute for Metals Research, Stockholm, Sweden.
    On Strength, Stiffness and Dent Resistance of Car Body Panels1993Report (Other academic)
  • 40.
    Asnafi, Nader
    Swedish Institute for Metals Research, Stockholm, Sweden.
    On Strength, Stiffness and Dent Resistance of Car Body Panels1993Conference paper (Other academic)
  • 41.
    Asnafi, Nader
    Gränges Technology, Finspång, Sweden.
    On stretch and shrink flanging of sheet aluminium by fluid forming1999In: Journal of Materials Processing Technology, ISSN 0924-0136, E-ISSN 1873-4774, Vol. 96, no 1-3, p. 198-214Article in journal (Refereed)
    Abstract [en]

    In this investigation, vertical stretch and shrink flanging of sheet aluminium by fluid forming are studied experimentally and theoretically. The theoretical part comprises both analytical modelling and finite-element simulations.

    The fracture limit in stretch flanging is determined by the plastic strain ratio, the strain hardening exponent, and the uniform strain. The greater the magnitude of these parameters, the greater will be the fracture limit.

    The maximum applied pressure determines the ’wrinkling’ limit in shrink flanging by fluid forming. The greater is this pressure, the greater ’wrinkling’ limit. This limit is certainly several times greater in magnitude than that in shrink flanging by conventional tools (a rigid punch and die).

  • 42.
    Asnafi, Nader
    Swedish Institute for Metals Research, Stockholm, Sweden.
    On Stretch and Shrink Flanging of Sheet Aluminium by Fluid Forming1996Report (Other academic)
  • 43.
    Asnafi, Nader
    Industrial Development Center/Volvo Cars Body Components, Olofström, Sweden .
    On Stretch and Shrink Flanging of Sheet Aluminium by Fluid Forming1998In: Proceedings, working groups meeting - IDDRG, International Deep Drawing Research Group: Genval, Benelux, June 15 - 16, 1998, 1998Conference paper (Other academic)
  • 44.
    Asnafi, Nader
    Industrial Development Centre, Olofström, Sweden.
    On tool stresses in cold heading of fasteners1999In: Engineering Failure Analysis, ISSN 1350-6307, E-ISSN 1873-1961, Vol. 6, no 5, p. 321-335Article in journal (Refereed)
    Abstract [en]

    In this investigation, attention was focused on the tool stresses that emerge during manufacturing of fasteners. These stresses were studied both experimentally and theoretically. The theoretical part comprised finite-element simulation. This simulation showed that the zone at the die insert profile radius is so heavily loaded that plastic deformation is initiated in this region. In the experimental part, the emerging strains were measured in the region close to the interface between the die insert and the stress ring. The correspondence is good between the theoretical and experimental strains in this region. In spite of this and although 20 fasteners were cold-forged, the die insert did not fracture. Forming at production facilities showed that the die insert cracked after 9080 parts were produced. The results obtained in this investigation and the test conducted at production facilities indicate that high cycle fatigue, and not monotomic rupture, is the main cause of tool fracture in practice.

  • 45.
    Asnafi, Nader
    Örebro University, School of Science and Technology.
    Proceedings of the 2nd International Conference on Material Engineering and Advanced Manufacturing Technology (MEAMT 2018)2018Conference proceedings (editor) (Refereed)
  • 46.
    Asnafi, Nader
    Volvo Car Corporation, Göteborg (and Olofström), Sweden .
    Proceedings of the IDDRG 2008 Conference: Best in class stamping, 16-18 June 2008, Olofström, Sweden2008Conference proceedings (editor) (Other academic)
  • 47.
    Asnafi, Nader
    Örebro University, School of Science and Technology.
    Proceedings of the International Conference on Mechanical, Electric and Industrial Engineering (MEIE2018)2018Conference proceedings (editor) (Refereed)
  • 48.
    Asnafi, Nader
    Volvo Car Corporation, Göteborg (and Olofström), Sweden.
    Proceedings of the international conference on recent advances in manufacture & use of tools & dies and stamping of steel sheets: October 5-6, 2004, Olofström, Sweden2004Conference proceedings (editor) (Other academic)
  • 49.
    Asnafi, Nader
    Örebro University, School of Science and Technology.
    Selective Laser heat Treatment to Tailor the Autobody Part Properties and Improve the Manufacturing Flexibility2019Conference paper (Other academic)
  • 50.
    Asnafi, Nader
    Örebro University, School of Science and Technology.
    Selective Laser heat Treatment to Tailor the Autobody Part Properties and Improve the Manufacturing Flexibility2019Conference paper (Other academic)
    Abstract [en]

    This investigation is focused on the stamping behaviour of boron steel, the properties of which are modified by selective laser heat treatment. Both CO2 and fibre lasers are tested. By using different laser processing parameters, the hardening depth in the 1 mm thick boron steel sheet Boloc 02 is varied. Four routes are tested and verified. The forming operation (in which a so-called flexrail beam is produced) in all four routes is conducted at ambient (room) temperature. The Reference route comprises stamping of the sheet. The GridBlank route starts with selective laser heat treatment of the blank, after which the blank is allowed to cool down, moved to a hydraulic press and stamped. In the GridTube route, the blank is first stamped, after which the part is moved to a laser cell and selectively laser heat treated. The fourth route, the RapidLaser route, is similar to the GridBlank route, but a higher laser speed is used to promote higher total productivity. The GridBlank route results in the highest hardness values and the best shape accuracy. The initial sheet material exhibits a hardness of 200 HV, while the parts produced in the GridBlank route exhibit a hardness of 700 HV.

123 1 - 50 of 116
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