3D Polymer Printing and its Integration into Manufacturing Systems

Photopolymer based additive manufacturing is currently growing at a rate of approx. 36% per year. When a maturing technology experiences exponential growth, leaps are taken with respect to the capabilities that the process brings to the industry. This talk will focus on the most recent technology advances within vat photopolymerization and the materials development that to a large extent is the main driver for new application areas for the technology. Learn the latest and greatest about what vat photopolymerization can do for your organization.

In recent years, DTU Mechanical Engineering has put an effort into changing the traditional tool production chain by maturing the so-called “soft tooling” method for making moulds. This method replaces the tool steel mould cavity in the injection moulding machine with a set of soft tool inserts made from polymer. Hereby, the machining time and cost is reduced significantly compared to conventional tooling processes based on milling, drilling, CNC tooling, etc. This talk will present the state- of-the-art of the soft-tooling process.

Additive Manufacturing (AM) has had a strong positive impact on product development and short-series production, but has achieved limited penetration into mainstream manufacturing due to an enduring lack of production-grade materials. Freeform Injection Molding combines the benefits from AM and injection molding, and allows manufacturers to deliver components in tried-and-trusted injection-moldable materials with the lead-times, start-up costs and design freedom from AM. In this talk, Lasse Staal shares experience with FIM to date, and ventures a guess at future perspectives.

Vat-photopolymerization additive manufacturing (VPAM) allows fast replication of high complexity and high precision geometries that are not possible to achieve with other conventional technologies. This study investigates how VPAM can be used to manufacture moulds for the lost-form technology. Two mould designs are investigated: freeform geometry replication for dental applications and tools with complex internal cooling channels. Finally, this study addresses the geometrical accuracy, limitations and challenges of VPAM in order to fully integrate it in the 3DIMS process chain.

The powder injection moulding industry is based on large volume production of high-precision parts. Using polymer moulds as those offered by the FIM concept (Freeform Injection Molding), small volume and even custom part production is possible, but the precision should be as high as that obtained for large volume production to cater to the industry. This talk covers some of the key parts of the journey towards that goal.

The use of the lost-form technology into the manufacturing process 3D-Printing Integrated Manufacturing System requires the use of low pressure during the injection moulding step. In order to reduce the pressure during moulding, new feedstock needs to be developed. This study shows the effect that slurry composition and powder particle size distribution has on the viscosity of the feedstock. Moreover, an investigation of the mould expansion during the demolding step will also be addressed. Finally, the study presents a two-step debinding process to effectively remove the binder from the moulded part. A particular focus will be spent on describing the geometrical variation and the formation of defects, such as porosities and cracks, during the different steps of the process.

We use 3D printing to produce soluble molds for percutaneous silicone implants. This gives design freedom to introduce interconnected pores and advanced geometries previously unobtainable. The motive for doing so is to reduce infections for patients living with long term or permanent percutaneous implants. In vivo studies on sheep are performed to asses efficacy of design and material changes.

This presentation will discuss a methodology to enable industrial end-users identify potential components for manufacturing with Freeform Injection Moulding (FIM) is discussed. A list of relevant factors including both the technical and economic criteria such as size, production volume, cost per part, etc. for part selection for FIM will be presented. The method will also incorporate the relationship of the chosen factors with the objectives which the company wants to consider for adopting FIM. This will be followed by a discussion of an appropriate Decision Support System (DSS) for filtering and ranking the parts will be discussed. Finally, it will be discussed how the part screening factors and method for part selection for FIM will differ from part selection for AM.

As additive manufacturing (AM) improves and becomes more widespread, being able to compare a manufactured part to it’s digital twin, becomes crucial. Such a comparison can be performed by combining calibrated photography with computer vision and computer graphics techniques. In this talk, we present a method for digitally recreating a scene’s layout by comparing photographs with rendered images. This enables users of AM to evaluate the quality of a manufactured part by direct comparison with it’s digital twin.

Transparent materials become more and more important for applications in which materials are subject to extremely high mechanical and thermal stresses, such as optoelectronics, solar cells, protective optics, dental and medical applications, etc. The processing of transparent materials via a sintering based process provides many advantages and at the same time some industrial challenges. The transparency can be affected by many properties including the part geometry, density, crystalline structure, surface roughness, grain size, defects, porosity, etc. This presentation will focus on the optimization of the sintering process to achieve required transparency of the sintered material and discuss some critical issues that have high influences on the transparency. An industrial case of a dental component will be used as the case study for this presentation.