| 16901. |
- Asnafi, Nader, 1960-
(författare)
-
Application of Laser-Based Powder Bed Fusion for Direct Metal Tooling
- 2021
-
Ingår i: Metals. - Basel, Switzerland : MDPI. - 2075-4701. ; 11:3
-
Tidskriftsartikel (refereegranskat)abstract
- 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.
|
|
| 16902. |
|
|
| 16903. |
- Asnafi, Nader, 1960-, et al.
(författare)
-
Automotive Stamping Tools & Dies and Injection Mold made by Additive Manufacturing through Laser-based Powder Bed Fusion
- 2019
-
Ingår i: Metal Additive Manufacturing Conference.
-
Konferensbidrag (refereegranskat)abstract
- Design and production of tools, dies and moulds 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 design and production of stamping tools & dies for sheet metal components and injection moulds for plastic components. Laser-based Powder Bed Fusion (LPBF) is the additive manufacturing (henceforth even called 3D printing) method used in this investigation.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 are approved/certified for stamping of 2 mm thick DP600. A working station in a progressive die used for stamping of 1 mm thick DP600 is 3D-printed in DIN 1.2709, both with a honeycomb inner structure and after topology optimization, with successful results. 3D printing results in a significant lead time reduction and improved tool material efficiency. The cost for 3D-printed stamping tools and dies is somewhat higher than the cost of those made conventionally. DIN 1.2709 is certified in this study as tool material for stamping of hot-dip galvanized DP600.The core (inserts) of an injection mould is 3D-printed in DIN 1.2709, conformal cooling optimized and 3D-printed in Uddeholm AM Corrax, and compared with the same core made conventionally. Additive manufacturing results in localized tool production and lower total costs. The cooling and cycle time can be improved significantly, if the injection moulding core (inserts) is optimized and 3D-printed in Uddeholm AM Corrax. The best results are obtained, if the 3D-printed core is NOT only an optimized copy of the conventionally designed and manufactured version. The best results are obtained, if the core is redesigned to utilize the full potential of 3D printing.This paper accounts for the results obtained in the above-mentioned investigations.
|
|
| 16904. |
|
|
| 16905. |
- Asnafi, Nader, 1960-, et al.
(författare)
-
Automotive tube bending and tubular hydroforming with extruded aluminium profiles
- 2000
-
Ingår i: SAE technical paper series. - 400 Commonwealth Drive, Warrendale, PA, United States : Society of Automotive Engineers. - 0148-7191.
-
Tidskriftsartikel (refereegranskat)abstract
- Side Member Left and Side Member Right, which go from bumper to bumper, were at the focus in the present study. These side members were produced using straight round (hollow with a circular cross-section) extruded aluminium profiles as tube material. The tubes were bent and hydroformed. Rotary-draw bending yielded the best result. A spread within 8 mm after bending was found to be acceptable provided that the bent tube was hydroformed with a high maximum internal pressure (1300 bars in this study). Pressure-assisted tool (hydroforming tool) closure should be preferred. Such a tool closure prevents formation of buckles, which may be difficult to straighten out completely during hydroforming. Planeness and parallelity of the press tables and adapters play a significant role, as far as the spread and inplaneness of hydroformed components are concerned. The hydroforming tool must be matched in the press that actually will be used. Proper evacuation (of particularly air) is essential, especially in long hydroforming tools. All cross sections must be deformed at least 2% (average perimeter enlargement), if the hydroformed components are to exhibit a reasonable spread. The critical (fracture) cross-sections predicted by finite-element simulation correspond to those found in practical tests. However, the finite-element simulation was not able to predict formation of wrinkles at the tube ends caused by excessively large strokes. Such wrinkles were obtained in practice.
|
|
| 16906. |
|
|
| 16907. |
- Asnafi, Nader, 1960-, et al.
(författare)
-
Blanking, stamping and trimming die experiences at volvo cars
- 2004
-
Ingår i: Proceedings of the International Conference on Recent Advances in Manufacture & Use of Tools & Dies and Stamping of Steel Sheets. - Olofström : Volvo Cars. ; , s. 263-274
-
Konferensbidrag (refereegranskat)abstract
- During the past years, large efforts have been made at Volvo Cars to establish a scientific and systematic approach to selection of die materials, hardening methods and surface treatments/coatings. These efforts were initiated, since both new higher strength sheet materials and new die materials with better performance were introduced. Both these higher strength sheet materials and higher performance die materials needed to be industrialized. At the same time, the die manufacturing and maintenance costs must be reduced. A relationship must also be established between the die materials, hardening methods and surface treatments/coatings selected on one side and the targeted volume sizes on the other. In this paper, some of the industrial cases studied at Volvo Cars will be presented. This study is, however, not completed yet The dies described in this paper (along with other dies) have been and will be monitored continuously. The authors have chosen to focus on the technology rather than the economy, particularly since the primary purpose of this paper is to share information with other technicians and discuss the feasibility of different technical solutions. Six blanking/trimming dies and seven stamping (forming) dies are presented in this paper.
|
|
| 16908. |
|
|
| 16909. |
- Asnafi, Nader, 1960-
(författare)
-
Design and Additive Manufacturing of Tools for Forming and Trimming of up to 2-mm Thick DP600
- 2020
-
Ingår i: Current Trends in Sheet Metal Forming.
-
Konferensbidrag (refereegranskat)abstract
- 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.
|
|
| 16910. |
|
|
