journal article·2025-10-11Open access

Cost-Efficient Injection Mold Design: A Holistic Approach to Leveraging Additive Manufacturing’s Design Freedom Through Topology Optimization

Julian Redeker, Hagen Watschke, Simon Wurzbacher, Josias Kayser, Karl Hilbig, Thomas Vietor, Okan Sezek, Christoph Gayer

Applied Sciences· Volume 15· Issue 20

Abstract

Additive manufacturing offers significant design freedom for injection mold tooling, particularly in optimizing cooling performance and reducing mass. This study presents a holistic framework for the topology optimization of mold inserts considering design for additive manufacturing principles, integrating essential boundary conditions from the mold making, injection molding process, and post-processing operations. A slider component with conformal cooling channels serves as the case study. Using simulation-driven design and finite element analysis, two design variants, based on conventional and modified design spaces, were evaluated. Mechanical loads from clamping and the injection process were considered, with safety factors applied to reflect industrial misuse scenarios. The topology optimization process was implemented using Altair OptiStruct and validated through displacement and stress analyses. The results show savings in both mass and costs of up to 60% while maintaining structural integrity under operational and misuse conditions. The maximum displacements—only a 4 µm increase compared to the reference—remained within DIN ISO 20457 tolerances, and stresses did not exceed 170 MPa under operational conditions, confirming industrial applicability. This study concludes with a proposed framework for integrating topology optimization into mold design workflows.
Source: crossref · Quality: baseline

Research context

OpenAlex topics: Additive Manufacturing and 3D Printing Technologies · Manufacturing Process and Optimization · Injection Molding Process and Properties

SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.

Affiliations

Institute for Engineering Design, Technische Universität Braunschweig, 38100 Braunschweig, Germany

Voestalpine HPM Deutschland Beteiligungs SE, 40213 Düsseldorf, Germany

Voestalpine Additive Manufacturing Center GmbH, 40213 Düsseldorf, Germany

Funding

Open Access Publication Funds of the Technische Universitat Braunschweig, Germany

References (67)

Show source-provided references
1. Schröder, T. (2022). Simulation in der Spritzgiesstechnik, Hanser.10.3139/9783446474628.fm ↗
2. Kazmer, D.O. (2007). Injection Mold Design Engineering, Hanser/Hanser Gardner Publ.10.3139/9783446434196.fm ↗
3. General frameworks for optimization of plastic injection molding process parameters10.1016/j.simpat.2013.11.003 ↗
4. Design and fabrication of conformal cooling channels in molds: Review and progress updates10.1016/j.ijheatmasstransfer.2021.121082 ↗
5. Rocha, S.B., Zhiltsova, T., Neto, V., and Oliveira, M.S.A. (2022). Optimization to Assist Design and Analysis of Temperature Control Strategies for Injection Molding-A Review. Materials, 15.10.3390/ma15124048 ↗
6. Wagner, G., and Nóbrega, J.M. (2025). Conformal Cooling Channels in Injection Molding and Heat Transfer Performance Analysis Through CFD—A Review. Energies, 18.10.3390/en18081972 ↗
7. Heat treatment and properties of a hot work tool steel fabricated by additive manufacturing10.1016/j.msea.2019.03.027 ↗
8. A comprehensive review on laser powder bed fusion of steels: Processing, microstructure, defects and control methods, mechanical properties, current challenges and future trends10.1016/j.jmapro.2021.12.033 ↗
9. Processability and cracking behaviour of novel high-alloyed tool steels processed by Laser Powder Bed Fusion10.1016/j.jmatprotec.2021.117435 ↗
10. Production Tools Made by Additive Manufacturing Through Laser-based Powder Bed Fusion10.1007/s00501-020-00961-8 ↗
11. Botero, C., Sjöström, W., Jimenez-Pique, E., Koptyug, A., and Rännar, L.-E. (2025). Small- to Large-Scale Electron Beam Powder Bed Fusion of Functionally Graded Steels. J. Manuf. Mater. Process., 9.10.3390/jmmp9010007 ↗
12. Influence of post treatment on microstructure, porosity and mechanical properties of additive manufactured H13 tool steel10.1016/j.msea.2018.08.046 ↗
13. Uddeholm AB (2025, September 05). Uddeholm Tyrax® ESR—Technical Datasheet. Available online: https://www.uddeholm.com/app/uploads/sites/216/productdb/api/uddeholm-tyrax-esr_tech_en.pdf.
14. Gibson, I., Rosen, D., and Stucker, B. (2015). Additive Manufacturing Technologies, Springer.10.1007/978-1-4939-2113-3 ↗
15. Warpage control of thin-walled injection molding using local mold temperatures10.1016/j.icheatmasstransfer.2014.12.008 ↗
16. Design Optimization of Plastic Injection Tooling for Additive Manufacturing10.1016/j.promfg.2017.07.082 ↗
17. Jahan, S.A., and El-Mounayri, H. (2018). A Thermomechanical Analysis of Conformal Cooling Channels in 3D Printed Plastic Injection Molds. Appl. Sci., 8.10.3390/app8122567 ↗
18. Design of Advanced Injection Mold to Increase Cooling Efficiency10.1007/s40684-019-00041-4 ↗
19. Torres-Alba, A., Mercado-Colmenero, J.M., Diaz-Perete, D., and Martin-Doñate, C. (2020). A New Conformal Cooling Design Procedure for Injection Molding Based on Temperature Clusters and Multidimensional Discrete Models. Polymer, 12.10.3390/polym12010154 ↗
20. Development of a Smart Plastic Injection Mold with Conformal Cooling Channels10.1016/j.promfg.2017.07.020 ↗
21. The Minerals, Metals & Materials Society (2019). A Mold Insert Case Study on Topology Optimized Design for Additive Manufacturing. Solid Freeform Fabrication 2019: Proceedings of the 30th Annual International Solid Freeform Fabrication Symposium, Austin, TX, USA, 12–14 August 2019, University of Texas at Austin. An Additive Manufacturing Conference.
22. Hartmann-H’Lawatschek (2025, September 05). Fertigungsfreiheit zur Topologieoptimierung genutzt: Toolcraft entwickelt 3D-gedrucktes Spritzgießwerkzeug. Kunststoffe, Available online: https://www.kunststoffe.de/a/fachartikel/fertigungsfreiheit-zur-topologieoptimier-323037.
23. PROTIQ GmbH (2025, September 05). More Efficient and Economic Injection Mold Tools thanks to Topology Optimization, CFD Simulation and 3D Printing: Success Story. Available online: https://altair.com/docs/default-source/resource-library/cs_us_protiq_e_letter_web_final.pdf?sfvrsn=eef3d88_3.
24. Numerical and experimental analysis of hydraulic and thermal performance in additively manufactured topology-optimized heat sinks with different geometric features10.1016/j.applthermaleng.2025.126619 ↗
25. Bhat, C., Prajapati, M.J., Kumar, A., and Jeng, J.-Y. (2024). Additive Manufacturing-Enabled Advanced Design and Process Strategies for Multi-Functional Lattice Structures. Materials, 17.10.3390/ma17143398 ↗
26. Recent advancement in conformal cooling channels: A review on design, simulation and future trends10.1016/j.cad.2025.103899 ↗
27. 3-Dimenional conformal cooling channel design: Origami-inspired topology optimization approach10.1016/j.applthermaleng.2024.122526 ↗
28. Topology optimization designed twisted conformal cooling channel for additive-manufactured hot-stamping tool10.1016/j.applthermaleng.2024.124784 ↗
29. An integration of topology optimization and conformal minimal surfaces for additively manufactured liquid-cooled heat sinks
30. Wu, T., and Tovar, A. (2018). Design for Additive Manufacturing of Conformal Cooling Channels Using Thermal-Fluid Topology Optimization and Application in Injection Molds. Volume 2B: 44th Design Automation Conference, Proceedings of the ASME 2018 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference, Quebec City, QC, Canada, 26–29 August 2018, American Society of Mechanical Engineers.10.1115/DETC2018-85511 ↗
31. Thermo-fluid Topology Optimization and Experimental Study of Conformal Cooling Channels for 3D Printed Plastic Injection Molds10.1016/j.promfg.2019.06.120 ↗
32. Thermofluid topology optimization for cooling channel design10.1016/j.applthermaleng.2023.121317 ↗
33. Additive manufacturing integration with topology optimization methodology for innovative product design10.1007/s00170-017-0112-9 ↗
34. Coranic, T., Gaspar, S., and Pasko, J. (2021). Utilization of Optimization of Internal Topology in Manufacturing of Injection Moulds by the DMLS Technology. Appl. Sci., 11.10.3390/app11010262 ↗
35. Additively manufactured injection mould tooling incorporating gradient density lattice structures for mass and energy reduction
36. (2018). Kunststoff-Formteile—Toleranzen und Abnahmebedingungen (ISO_20457:2018): Toleranzen und Abnahmebedingungen (ISO_20457:2018) (Standard No. ISO 20457:2021-06).
37. Multidisciplinary robust and reliability-based design optimization of injection molding system10.1007/s12008-022-01139-x ↗
38. Lightweight injection mold using additively manufactured Ti-6Al-4V lattice structures10.1016/j.jmapro.2022.05.022 ↗
39. A Framework for Optimizing the Design of Injection Molds with Conformal Cooling for Additive Manufacturing10.1016/j.promfg.2015.09.049 ↗
40. Implementation of Conformal Cooling & Topology Optimization in 3D Printed Stainless Steel Porous Structure Injection Molds10.1016/j.promfg.2016.08.077 ↗
41. Multiscale, thermomechanical topology optimization of self-supporting cellular structures for porous injection molds10.1108/RPJ-09-2017-0190 ↗
42. A survey of manufacturing oriented topology optimization methods10.1016/j.advengsoft.2016.07.017 ↗
43. Sutradhar, A., Park, J., Haghighi, P., Kresslein, J., Detwiler, D., and Shah, J.J. (2017). Incorporating Manufacturing Constraints in Topology Optimization Methods: A Survey. Volume 1: 37th Computers and Information in Engineering Conference, Proceedings of the ASME 2017 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference, Cleveland, Ohio, USA, 6–9 August 2017, American Society of Mechanical Engineers.10.1115/DETC2017-68192 ↗
44. Rodrigues, H.C., Herskovits, J., Mota Soares, C.M., Araújo, A.L., Guedes, J.M., Folgado, J.O., Moleiro, F., and Madeira, J.F.A. (2019). Adaptive Topology and Shape Optimization with Integrated Casting Simulation. EngOpt 2018 Proceedings of the 6th International Conference on Engineering Optimization, Springer International Publishing.10.1007/978-3-319-97773-7 ↗
45. A Survey of Topology Optimization Methods Considering Manufacturable Structural Feature Constraints for Additive Manufacturing Structures10.1016/j.amf.2024.200143 ↗
46. Level set-based topology optimization with overhang constraint: Towards support-free additive manufacturing10.1016/j.cma.2018.04.040 ↗
47. Current and future trends in topology optimization for additive manufacturing10.1007/s00158-018-1994-3 ↗
48. A review of topology optimization for additive manufacturing: Status and challenges10.1016/j.cja.2020.09.020 ↗
49. An additive manufacturing filter for topology optimization of print-ready designs10.1007/s00158-016-1522-2 ↗
50. Topology optimization considering overhang constraints: Eliminating sacrificial support material in additive manufacturing through design10.1007/s00158-016-1551-x ↗
51. Undercut and overhang angle control in topology optimization: A density gradient based integral approach10.1002/nme.5461 ↗
52. Hoglund, R., and Fabian, F. (2025, September 05). Design Optimization for Additive Manufacturing in OptiStruct with consideration of Overhang Angle in Topology Optimization. Available online: https://altair.com/docs/default-source/resource-library/design-optimization-for-am-in-optistruct-with-consideration-of-oha-in-topology-optimization.pdf?sfvrsn=f951db3d_3.
53. Simultaneous optimization of build orientation and topology for additive manufacturing
54. Design for additive manufacturing: 3D simultaneous topology and build orientation optimization10.1007/s00158-020-02590-8 ↗
55. 3D topology optimization for cost and time minimization in additive manufacturing10.1007/s00158-019-02392-7 ↗
56. Support structure design in additive manufacturing based on topology optimization10.1007/s00158-017-1743-z ↗
57. Topology optimization of support structure layout in metal-based additive manufacturing accounting for thermal deformations10.1007/s00158-020-02512-8 ↗
58. Topology and build orientation optimization for additive manufacturing considering build height and overhang area10.1007/s00158-024-03808-9 ↗
59. Topology optimization incorporating a passageway for powder removal in designs for additive manufacturing10.1007/s00158-022-03280-3 ↗
60. Topology optimization method with elimination of enclosed voids10.1007/s00158-019-02204-y ↗
61. Achieving self-supported enclosed voids and machinable support structures in topology optimization for additive manufacturing10.1007/s00158-024-03858-z ↗
62. LyondellBasell Industries (2025, September 05). Moplen EP448T—Technical Datasheet. Available online: https://www.materialdatacenter.com/mb/.
63. SPE-Inspiring Plastics Professionals (2025, January 3–6). Warpage control through parallel conformal cooling channels. Proceedings of the SPE Annual Technical Conference—ANTEC 2025, Philadelphia, PA, USA.
64. Brebbia, C.A., Orszag, S.A., Argyris, J., Bathe, K.-J., Cakmak, A.S., Connor, J., McCrory, R., Desai, C.S., Holz, K.-P., and Leckie, F.A. (1989). The Three Columns for Treating Problems in Optimum Structural Design. Optimization: Methods and Applications, Possibilities and Limitations, Springer.
65. Optimization of clamping force for low-viscosity polymer injection molding10.1016/j.polymertesting.2020.106700 ↗
66. Hopmann, C., Menges, G., Michaeli, W., and Mohren, P. (2018). Spritzgießwerkzeuge: Auslegung, Bau, Anwendung, Hanser. [7th ed.]. Neu Bearbeitete Auflage.10.1007/978-3-446-45390-6 ↗
67. Grote, K.-H., Bender, B., and Göhlich, D. (2018). Dubbel, Springer.10.1007/978-3-662-54805-9 ↗