Bertelsen, J. G.

Davoudinejad, A.

Li, D.

M. Ribo, M.

Regi, F.

Thorn, S.

Zhang, Y.

Mask projection vat photopolymerization technology provides a method for additive manufacturing (AM) of high resolution surface features. In the present project, the technology is used to generate injection moulding inserts containing a double-curved freeform surface with bi-directional reflectance patterns. Orienting these patterns 0° and 90° relative to the viewing direction generates surface contrast with “dark” and “bright” areas (Fig 1). This allows for incorporation of information barcodes in the polymer insert which subsequently replicates into every injection moulded part for e.g. enhanced product traceability, B2B information or end-user interaction at a significant reduction inlead-time compared to conventional tooling of inserts

Online Research Database In Technology

  General rights Copyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights.   Users may download and print one copy of any publication from the public portal for the purpose of private study or research.  You may not further distribute the material or use it for any profit-making activity or commercial gain  You may freely distribute the URL identifying the publication in the public portal  If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim.         Downloaded from orbit.dtu.dk on: Mar 30, 2019Dimensional Accuracy and Repeatability of 3D Printed Mould Inserts by DLPThorn, S. ; Bertelsen, J. G. ; Mendez Ribo, Macarena; Li, D. ; Regi, Francesco; Davoudinejad, Ali; Zhang,YangPublication date:2018Document VersionPublisher's PDF, also known as Version of recordLink back to DTU OrbitCitation (APA):Thorn, S., Bertelsen, J. G., M. Ribo, M., Li, D., Regi, F., Davoudinejad, A., & Zhang, Y. (2018). DimensionalAccuracy and Repeatability of 3D Printed Mould Inserts by DLP. Poster session presented at Euspen SpecialInterest Group Meeting 2018: Structured & Freeform Surfaces, Cachan, France.Dimensional Accuracy and Repeatability of 3D Printed Mould Inserts by DLP S. Thorn1, J.G. Bertelsen1, M.M. Ribo1, D. Li1, F. Regi1, A. Davoudinejad1, Y. Zhang1 1Technical University of Denmark silastjensen@outlook.com ; jacobgsb@gmail.com  Abstract Mask projection vat photopolymerization technology provides a method for additive manufacturing (AM) of high resolution surface features. In the present project, the technology is used to generate injection moulding inserts containing a double-curved freeform surface with bi-directional reflectance patterns. Orienting these patterns 0° and 90° relative to the viewing direction generates surface contrast with “dark” and “bright” areas (Fig 1). This allows for incorporation of information barcodes in the polymer insert which subsequently replicates into every injection moulded part for e.g. enhanced product traceability, B2B information or end-user interaction at a significant reduction in lead-time compared to conventional tooling of inserts.  The barcode feature layer is manufactured onto a double-curved sinusoidal surface to simulate a complex surface of any given product. It has a peak-to-peak distance of 520µm and consists of 98.02µm x 98.02µm x 20µm cuboids. Bi-directional reflectance is generated by a triangular prism with a height of 17.28μm and slope of 10° on top of each cuboid (Fig 2). The project pushes the resolution limit of AM by utilising a custom built unit at DTU1. A study into the effect of UV exposure on 1µm and 625nm layer thickness’ has been conducted with highest verified resolution achieved at the present moment to be voxel size of 7.54μm x 7.54μm x 4μm.  The study showed that replication is highly dependent on the amount of UV exposure. Highest surface contrast was achieved with a radiant exposure E = 12mJ/cm2 in troughs of the freeform surface however large areas of the surface were detached from midline to peak due to overexposure. Using E = 2mJ/cm2 generates a uniformly covered reflectance surface with few defects. Metrological measurements of parts created with 1µm and 625nm layer thickness yield low surface roughness with Ra values ~50-100nm. Figure 1 - Post-cured polymer insert with minor defects. Figure 2 - Optical profilometry of reflectance patterns show low deviations compared to nominal dimension. 

Dimensional Accuracy and Repeatability of 3D Printed Mould Inserts by DLP

http://orbit.dtu.dk/ws/files/163011075/Euspen2018ShortAbstract_1_.pdf

Dimensional Accuracy and Repeatability of 3D Printed Mould Inserts by DLP

Abstract

Similar works

Full text

Available Versions

Online Research Database In Technology