Forum AM Science II

WEDNESDAY, 23 June 2021

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09:00 - 09:05
Welcome from the Rapid.Tech 3D Live-TV-Studio
09:05 - 09:15
Welcome from the Rapid.Tech 3D Live-TV-Studio
09:15 - 09:45

The aerospace industry is characterized by small quantities, the highest safety requirements and, more than almost any other industry, by the need to save weight. Every reduced kilogram of weight saves up to 3 kg of CO2 - and that on a daily basis. Moreover, the short-term supply of spare parts is quite challenging. That is why aerospace industry is ideal for the introduction of components that are topologically optimized and manufactured by 3D printing processes. For more than 10 years, parts have been converted from conventional design and manufacturing to additive processes. The results are clear: components become lighter, smaller and may even integrate more functions.

Nevertheless, the conversion process is progressing slowly. There are several reasons, starting first and foremost with the demand for maximum safety. With existing design and production processes, all necessary qualifications are available for the required safety of components. For 3D printing, unfortunately, we are still at the beginning and, therefore, invest a lot of time and energy in process qualifications. We have to ensure that the internal structures and the surfaces meet all the requirements for permanent, safe operations. In parallel, we are, of course, continuing to work on optimizing the processes, on new material combinations and design processes, because we are certain that 3D printing will be indispensable for the climate-neutral aircraft of the future.

Volker Thum | BDLI Bundesverband der Deutschen Luft- und Raumfahrtindustrie e.V.

Volker Thum

09:45 - 09:50
Greetings from the Rapid.Tech 3D Live-TV-Studio
09:50 - 10:00
Break & Chat Roulette
10:00 - 10:30

In recent years the gas flow in L-PBF process chambers has been identified as highly relevant for repeatability and robustness of the process. Thus, by affecting part quality and reducing the scrap rate, it improves the sustainability of this AM technology. This topic gets even more relevant for multi-laser full-field systems due to the increasing laser-particle interaction. The assessment of quality and effectiveness of the gas flow and suited multi laser processing strategy is currently done by repetitive production and analysis of test samples. In order to reduce this effort, a fundamental understanding of the impact of laser beam-plume interaction on the laser beam properties and their measurement in order to quantify the impact is needed. For this purpose, the in-process online laser-beam diagnostics during laser beam – plume interaction will be applied. Moreover, the performance of the gas flow concept will be reviewed by in-process measurement of particle load in the atmosphere of the process chamber.

Dr. Wilhelm Meiners | Trumpf Laser- und Systemtechnik GmbH

 Dr. Wilhelm Meiners

10:30 - 11:00

The usage of low-cost powder and low flowability, but also the application of

multi-material powder layers, in additive manufacturing requires a rethinking

of the mechanisms of powder application. Electrostatics and electrophotography

offer great potential for powder coating in laser-based powder bed fusion

(LPBF) processes. Depending on the progress in powder application, the

aim is to maintain the charge on the photoconductor surface, the targeted local

or complete discharge of the photoconductor. For experimental investigations

a prototype was designed and a test environment for defined illumination was

created. The evaluation concentrated on the elementary process phase of the

electrostatic charging of the photoconductor. The findings are used to identify

opportunities and risks for the subsequent process steps and for the transfer

of the mechanism to a LPBF machine and to derive boundary conditions.

Julia Förster | Fraunhofer IGCV

Julia Förster

11:00 - 11:30

For the successful production of additively manufactured components, support structures are necessary to prevent the melt from sinking in the case of overhangs, to fix the component to be produced on the build platform and to reduce residual stresses. However, since support structures are not part of the functional component, their resource-efficient use is essential. To achieve this, their volume must be reduced without impairing their function. Various approaches are being pursued to achieve this goal, with computer-aided development of novel support structures in particular offering great potential. Here, it is important to know physical limits such as the maximum distance between two connection points of a support structure to the component. This is determined experimentally in the present study for cylindrical support structures made of Ti6Al4V. The structure diameter, the structure spacing, the overhang angle and the process parameters are included as influencing factors. Optical measurements provide information on dimensional accuracy and porosity of the specimens and thus on the support structure properties. From the empirical data, a design guideline is derived in the form of a process map guiding the user towards suitable combinations, which can later also be integrated in the form of numerical rules in the computer-aided generation of support structures. 

Karim Asami | iLAS Institut für Laser- und Anlagensystemtechnik, Technische Universität Hamburg

Karim Asami

11:30 - 12:00

This paper demonstrates that unplanned failures of metal-based additive manufacturing systems (LBM systems) in the early stages of production can be predicted by using artificial intelligence, resulting in significant cost savings. The economic impact was determined using a novel cost model and applied in an analytics project applying the CRISP-DM approach, which was based on comprehensive data sets of several thousands of build jobs from LBM systems that produced metal parts from a wide range of industrial sectors. A model comparison was carried out to identify the best prediction performance using the gradient boosted tree model and then optimised using XGBoost, resulting in excellent forecasting quality in the first 3-6 hours of the production stage. Cost savings of 10-40 % were estimated on the basis of this model. The decision-making process of the black-box model was revealed with the help of SHAP visualisations. The required exchange of data between all the participants in the additive value-added chain for the implementation of such analytics projects may generate further competitive advantages, thus paving the way for additive production to reach industrial mass production.

Daniel Beck | Bionic Production GmbH

Daniel Beck

12:00 - 12:30
Lunch break
12:30 - 13:00

Innovative bio-based materials and new manufacturing technologies can make a substantial contribution to conserving resources. Such a path can be taken by adapting Additive Manufacturing processes for the use of renewable/residual materials. For those materials we decided to develop an upcycling strategy and make use of their individual properties at the same time. This article describes the printing by Binder Jetting (3D Printing, 3DP) of comminute peach kernels with several binders, like polyvinyl alcohol (PVA), sugar, flour and lignosulfonate. After material processing (pre-comminution, separating the seeds and milling), the printable powder is analysed and mixed with the binder. Parts manufactured from such materials have a high decomposition rate measured in hours when exposed to water, making them ideal for applications such as unique single use packaging or short-lifetime products. To get stable parts, different peach/binder concentrations were investigated. Densities, decomposition rate and strength were measured at test specimens. Thus, acceptable printing results could be achieved by specific adjustment of the parameters. To further increase strength of the printed bodies, suitable coatings will be investigated in the future.

Dr. Lisa Kühnel | TU Bergakademie Freiberg, Chair of Additive Manufacturing

Dr. Lisa Kühnel

13:00 - 13:30

A methodology for the systematic evaluation of the material-specific human-toxic hazards in the application of additive manufacturing processes is developed within this paper. The components of the material are evaluated, on the one hand, in terms of the assigned hazard statements (so-called H phrases) and, on the other hand, in terms of the material handling and the protective precautions per process. Subsequently, the methodology is validated for the additive manufacturing processes of material extrusion and laser beam melting based on three ma-terials and two manufacturing systems each. This shows that the greatest human-toxic hazard occurs in the system preparation process within laser beam melting. In comparison, the human-toxic hazard in material extrusion is significantly lower.

Alexander Mahr | Fraunhofer-Institut für Produktionstechnik und Automatisierung IPA

Alexander Mahr

13:30 - 14:00

The main target of the ZIM-research project “4-axis FLM (ZF4104910PO8)” was to develop an additive manufacturing device and process for the production of symmetric and asymmetric rotational parts. The extrusion-based Additive Manufacturing (EAM) shall be able to transform thermoplastic filaments as well as reactive pasteous multicomponent materials simultaneously.

In the EAM process, a thermoplastic filament is typically transformed layer by layer in a two and a half -dimensional way using a constant and fixed layer height in z-direction. The most common materials are polylactic acid (PLA) and acrylonitrile butadiene styrene copolymer (ABS) and other amorphous thermoplastic materials.

For the development of the reactive build-process a low-cost EAM-device – the 3DGence ONE - is additionally equipped with a two-component endless plunger pump-system. The repetier firmware is changed by 3DGence for the control of the component A and component B in a ration between 1:10 till 1:1. The utilisation of the eccentric worm-drive pump ViscoDUO FFD 4/4 permits the dosing of highly viscous fluids without entering shear stress to the material. The two-component- polyurethane-system ADEKIT 236-25 shall be transformed into dimensional stable parts without using an additional in-line-activation system.

After tensile-testing the so generated specimen and analysing the chemical characteristics using Fourier Transform Infrared spectroscopy (FT-IR) the target of realising nearly isotropic mechanical properties can be approved. The mechanical properties are found on a level, that is comparable to the material data sheet values. Validating the degree of cross linking qualitatively by FT-IR analysis also verifies the functionality of the reactive EAM-process for generating mechanically isotropic part properties. 

Dr.-Ing. Jens Butzke | Institut für Kunststofftechnik Darmstadt (ikd)

Dr.-Ing. Jens Butzke 

14:00 - 14:15
Coffee break and Chat Roulette
14:15 - 16:15
Live Stream: Forum "AM in Construction Engineering & Architecture"
16:15 - 16:30
Coffee break and Chat Roulette
15:45 - 16:15

Die Praesentation stellt die Moeglichkeiten und Herausforderungen der Integration der AM-Technologie in das Boeing 777X Folding Wingtip System anhand eines Hydraulikaktuators dar.
Die Fallstudie zeigt, wie Liebherr Herausforderungen wie thermische Spannungen in der Produktion, Druckabfaelle im Betrieb, Oberflaechenbehandlung und Verschleißeoberflaechen von Titanaktuatoren begegnet.

Darüber hinaus wird ein Ausblick auf die Herausforderungen der Technologie und die Umsetzung hochintegrierter Komponenten in die Serienfertigung gegeben.

Alexander Altmann | Liebherr-Aerospace Lindenberg GmbH

Get more information about the forum "AM Science I"?

Tuesday, 22 June 2021

16:30 - 17:00

The Presentation highlights opportunities and challenges of incorporating AM technology on the Boeing 777X Folding Wingtip System Secondary Lock Actuator.

The Case Study shows how Liebherr addressed challenges like thermal stresses in production, pressure drops in operation, surface treatment and wear surfaces of titanium cylinders.
Furthermore, an outlook will be provided regarding the challenges of the technology and the implementation to serial production of highly integrated components.

Alexander Altmann | Liebherr-Aerospace Lindenberg GmbH

Get more information about the forum "AM Science I"?

Tuesday, 22 June 2021