Additive Fertigung
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- Additive manufacturing (15)
- Additive Manufacturing (12)
- Laser powder bed fusion (7)
- Thermography (7)
- Laser Metal Deposition (4)
- Laser Powder Bed Fusion (4)
- Inconel 718 (3)
- L-PBF (3)
- Laser metal deposition (3)
- Selective Laser Melting (3)
- 316L (2)
- AlSi10Mg (2)
- Directed Energy Deposition (2)
- Hybrid components (2)
- In-situ monitoring (2)
- Infrared thermography (2)
- Porosity (2)
- Position detection (2)
- Process monitoring (2)
- Residual stress (2)
- Selective laser melting (2)
- 3D Druck (1)
- 3D printing (1)
- AM (1)
- Active thermography (1)
- Additive Fertigung (1)
- Additive Manufacturing (AM) (1)
- Additive manufacturing (AM) (1)
- Advanced Manufacturing (1)
- Aerosol measurements (1)
- Air-coupled ultrasonic testing (1)
- Alumina (1)
- Analytical model (1)
- Anisotropy (1)
- Artificial weathering (1)
- Atmospheric pressure plasma (1)
- Bridging voids (1)
- Build direction (1)
- Build-up Orientation (1)
- Calculation time (1)
- Camera calibration (1)
- Cold Spray (1)
- Computer Aided Manufacturing (1)
- Copper powder particles (1)
- Crystal plasticity (1)
- Cyclic R-curve (1)
- DED (1)
- Data Integrity (1)
- Defect Detection (1)
- Defect detection (1)
- Design for Additive Manufacturing (DfAM) (1)
- Dielectric properties (1)
- Diffraction (1)
- Digital Twin (1)
- Digitalisation (1)
- Direct energy deposition (1)
- Directed energy deposition (1)
- Distortion simulation (1)
- Edge effects (1)
- Efficient modelling (1)
- Electrical conductivity (1)
- European Metrology Network (EMN) (1)
- Fatigue crack growth (1)
- Fume (1)
- Gas discharges (1)
- Haynes 282 (1)
- Heat accumulation (1)
- Heat treatment (1)
- Heat treatments (1)
- High-resolution camera (1)
- High-strength structural steels (1)
- Hybrid Part (1)
- Hybrid build-up (1)
- Hybrid repair (1)
- IN718 (1)
- ISRU (1)
- Infrastructure (1)
- Keyhole porosity (1)
- LMD (1)
- LW (1)
- Laboratory specimens (1)
- Large electrical high-voltage machine (1)
- Laser Powder Bed Fusion (L-PBF) (1)
- Laser Powder Bed Fusion (PBF-LB/M) (1)
- Laser Pulver Auftragsschweißen (1)
- Laser Welding (1)
- Laser beam melting (LBM) (1)
- Laser powderbed fusion (1)
- Laser thermography (1)
- Laser welding (1)
- Liquation Cracking (1)
- Lunar habitat (1)
- MPI (1)
- MPLS (1)
- Machine Learning (1)
- Magnetic swimmers (1)
- Maritime Components (1)
- Mechanical properties (1)
- Melt-pool-monitoring (1)
- Metrology (1)
- Micro-CT (1)
- Multispectral thermography (1)
- Neutron diffraction (1)
- Nickel-based superalloy (1)
- Nondestructive Testing (1)
- Nondestructive testing (1)
- Optical tomography (1)
- PBF-LB/M (1)
- PBF/LB-M (1)
- Particle gas emission (1)
- Path planning (1)
- Paving (1)
- Plasma acoustics (1)
- Plume (1)
- Polymer (1)
- Pores (1)
- Powder Analysis (1)
- Pre-weld Preparation (1)
- ProMoAM (1)
- Process Chain Integration (1)
- Process parameter optimization (1)
- Quality Assurance (1)
- Recycling (1)
- Repair of gas turbine blades (1)
- Reproducibility (1)
- Residual Stress (1)
- Residual Stresses (1)
- Residual stresses (1)
- Round robin (1)
- SLM (1)
- SWIR camera (1)
- Scale-bridging (1)
- Selective Laser Melting (SLM) (1)
- Selective laser melting (SLM) (1)
- Solar sintering (1)
- Solidification behaviour (1)
- Spatter (1)
- Stainless Steel (1)
- Strategic Research Agenda (SRA) (1)
- Supportless (1)
- Synchrotron X-ray diffraction (1)
- TES (1)
- Temperature behavior (1)
- Temperature emissivity separation (1)
- Tensile performance (1)
- Thermal Spray (1)
- Thermografie (1)
- Ti-6Al-4V (1)
- Time over threshold (1)
- Two-Photon Polymerization (1)
- Vickers hardness (1)
- Virtual experiments (1)
- Wire Arc Additive Manufacturing (1)
Organisationseinheit der BAM
- 9 Komponentensicherheit (28)
- 8 Zerstörungsfreie Prüfung (18)
- 9.6 Additive Fertigung metallischer Komponenten (13)
- 8.0 Abteilungsleitung und andere (11)
- 9.3 Schweißtechnische Fertigungsverfahren (10)
- 8.5 Röntgenbildgebung (7)
- 5 Werkstofftechnik (5)
- 9.4 Integrität von Schweißverbindungen (5)
- 5.0 Abteilungsleitung und andere (2)
- 5.4 Multimateriale Fertigungsprozesse (2)
Defects are still common in metal components built with Additive Manufacturing (AM). Process monitoring methods for laser powder bed fusion (PBF-LB/M) are used in industry, but relationships between monitoring data and defect formation are not fully understood yet. Additionally, defects and deformations may develop with a time delay to the laser energy input. Thus, currently, the component quality is only determinable after the finished process.
Here, active laser thermography, a nondestructive testing method, is adapted to PBF-LB/M, using the defocused process laser as heat source. The testing can be performed layer by layer throughout the manufacturing process. We study our proposed testing method along experiments carried out on a custom research PBF-LB/M machine using infrared (IR) cameras.
Our work enables a shift from post-process testing of components towards in-situ testing during the AM process. The actual component quality is evaluated in the process chamber and defects can be detected between layers.
Hybrid additive manufacturing is becoming increasingly important in the field of additive manufacturing. Hybrid approaches combine at least two different manufacturing processes. The focus of this work is the build-up of geometries onto conventionally manufactured parts using Powder Bed Fusion with Laser Beam of Metals (PBF-LB/M). The hybrid build-up requires a precise position detection system inside the PBF-LB/M machines to determine the exact position of the existing component. For this purpose, high-resolution camera systems can be utilized. However, the use of a camera system is associated with several challenges. The captured images are subject to various distortions of the optical path. Due to these distortions, it is not possible to use the images for measurements and, therefore, it is not possible to calculate the positions of objects. In this study a homography matrix is calculated to correct keystone distortion in the images. Different calibration patterns have been tested for the calculation of the homography matrix. The influence of the number of calibration points on the precision of position detection of objects is determined. Furthermore, the influence of an additional camera calibration by using ChArUco boards is evaluated. The result is a camera calibration workflow with associated calibration pattern for a precise position detection of parts inside PBF-LB/M machines allowing a hybrid build-up with minimum physical offset between base component and build-up.
The European Commission has identified Advanced Manufacturing and Advanced Materials as two of six Key Enabling Technologies (KETs). It is considered that Metrology is a key enabler for the advancement of these KETs. Consequently, EURAMET, the association of metrology institutes in Europe, has strengthened the role of Metrology for these KETs by enabling the creation of a European Metrology Network (EMN) for Advanced Manufacturing. The EMN is comprised of National Metrology Institutes (NMIs) and Designated Institutes (DIs) from across Europe and was formally established in October 2021. The aim of the EMN is to provide a high-level coordination of European metrology activities for the Advanced Manufacturing community.
The EMN itself is organized in three sections representing the major stages of the manufacturing chain: 1) Advanced Materials, 2) Smart Manufacturing Systems, and 3) Manufactured Components & Products. The EMN for Advanced Manufacturing is engaging with stakeholders in the field of Advanced Manufacturing (large companies & SMEs, industry organisations, existing networks, and academia), as well as the wider Metrology community, including Technical Committees, to provide input for the Strategic Research Agenda (SRA) on Metrology for Advanced Manufacturing.
This contribution will give an overview about the first version of the SRA prepared by the EMN for Advanced Manufacturing
Rapidly advancing technologies and progressive digitisation are posing challenges to the established quality infrastructure (QI). In response, the key stakeholders of the German QI established the initiative QI-Digital aimed at developing new solutions for modern quality assurance. One of the central use cases herein is quality assurance for additive manufacturing, in which a fully interlinked additive manufacturing process chain is established. The intention is to collect and process data from each production step, allowing for a comprehensive digital view of the physical material flow. Within this process chain, prototypes of digital QI tools like machine readable standards and digital quality certificates are being demonstrated, tested, and evolved. This is complemented by research on the process level, comprising the evaluation and refinement of methods for in-situ and ex-situ quality assurance, as well as algorithms for registration, reduction, and analysis of process data. This paper presents the status, goals, and vision for the QI-Digital use case additive manufacturing.
New developments in nickel-based superalloys and production methods, such as the use of additive manufacturing (AM), can result in innovative designs for turbines. It is crucial to understand how the material behaves during the AM process to advance industrial use of these techniques. An analytical model based on reaction-diffusion formalism is developed to better explain the solidification behavior of the material during laser metal deposition (LMD). The well-known Scheil-Gulliver theory has some drawbacks, such as the assumption of equilibrium at the solid-liquid interface, which is addressed by this method. The solidified fractions under the Scheil model and the pure equilibrium model are calculated using CALPHAD simulations. Differential scanning calorimeter is used to measure the heat flow during the solid-liquid phase transformation, the result of which is further converted to solidified fractions. The analytical model is compared with all the other models for validation.
Great complexity characterizes Additive Manufacturing (AM) of metallic components via laser powder bed fusion (PBF-LB/M). Due to this, defects in the printed components (like cracks and pores) are still common. Monitoring methods are commercially used, but the relationship between process data and defect formation is not well understood yet. Furthermore, defects and deformations might develop with a temporal delay to the laser energy input. The component’s actual quality is consequently only determinable after the finished process.
To overcome this drawback, thermographic in-situ testing is introduced. The defocused process laser is utilized for nondestructive testing performed layer by layer throughout the build process. The results of the defect detection via infrared cameras are shown for a research PBF-LB/M machine.
This creates the basis for a shift from in-situ monitoring towards in-situ testing during the AM process. Defects are detected immediately inside the process chamber, and the actual component quality is determined.
For the wide acceptance of the use of additive manufacturing (AM), it is required to provide reliable testing methods to ensure the safety of the additively manufactured parts. A possible solution could be the deployment of in-situ monitoring during the build process. However, for laser powder bed fusion using metal powders (PBF-LB/M) only a few in-situ monitoring techniques are commercially available (optical tomography, melt pool monitoring), which have not been researched to an extent that allows to guarantee the adherence to strict quality and safety standards.
In this contribution, we present results of a study of PBF-LB/M printed parts made of the nickel-based superalloy Haynes 282. The formation of defects was provoked by local variations of the process parameters and monitored by thermography, optical tomography and melt pool monitoring. Afterwards, the defects were characterized by computed tomography (CT) to identify the detection limits of the used in-situ techniques.
Laser-based Powder Bed Fusion of Metal (PBF-LB/M) is a broadly used metal additive manufacturing (AM) method for fabricating complex metallic parts, whose sizes are however limited by the build envelope of PBF-LB/M machines. Laser welding arises as a valid joining method for effectively integrating these AM parts into larger assemblies.
PBF-LB/M components must usually be stress-relieved before they can be separated from the build plate. An additional heat treatment can be beneficial for obtaining homogeneous mechanical properties across the seam or for the formation of desired precipitations in nickel-based-alloys.
Therefore, the tensile performance of laser welded hybrid (AM/wrought) and AM-AM tensile samples of Inconel 718 is examined after undergoing three different heat treatments and considering three relevant build directions. It can be shown that the build orientation is an influencing factor on weld properties even after two applied heat treatments.
The industrialization of AM is only possible by creating synergy with the tools of Industry 4.0. The system technology of Powder Bed Fusion with Laser beam of Metals (PBF-LB/M) reached a level of high performance in terms of process stability and material spectrum in the past years. However, the digital process chain, starting from CAD via CAM and plant-specific compila-tion of the manufacturing file exhibits media disruptions. The consequence is a loss of metadata. A uniform data scheme of simulation for Design for Additive Manufacturing (DfAM), the PBF-LB/M process itself and quality assurance is currently not realized within industry. There is no entity in the common data flows of the process chains, that enables the integration of these functionalities. As part of the creation of a digital quality infrastructure in the QI-Digital pro-ject, an integration of the CAD/CAM chain is being established. The outcome is a file in an advanced commercially available format which includes all simula-tions and manufacturing instructions. The information depth of this file extends to the level of the scan vectors and allows the automatic optimization and holis-tic documentation. In addition, the KPI for the economic analysis are generated by compressing information into a unique file combined with the application of a digital twin. The implementation and advantages of this solution are demon-strated in a case study on a multi-laser PBF-LB/M system. A build job contain-ing a challenging geometry is thermally simulated, optimized, and manufac-tured. To verify its suitability for an Additive Manufacturing Service Platform (AMSP), the identical production file is transferred to a PBF-LB/M system of another manufacturer. Finally, the achieved quality level of the build job is evaluated via 3D scanning. This evaluation is carried out in the identical entity of the production file to highlight the versatility of this format and to integrate quality assurance data.
Safety-critical applications of products manufactured by laser powder bed fusion (PBF-LB/M) are still limited to date. This is mainly due to a lack of knowledge regarding the complex relationship between process, structure, and resulting properties. The assurance of homogeneity of the microstructure and homogeneity of the occurrence and distribution of defects within complexly shaped geometries is still challenging. Unexpected and unpredicted local inhomogeneities may cause catastrophic failures. The identification of material specific and machine specific process parameter windows for production of fully dense simple laboratory specimens is state of the art. However, the incorporation of changing thermal conditions that a complexly shaped component can be faced with during the manufacturing process is often neglected at the stage of a process window determination. This study demonstrates the tremendous effect of changing part temperatures on the defect occurrence for the broadly used stainless steel alloy AISI 316L. Process intrinsic variations of the surface temperature are caused by heat accumulation which was measured by use of a temperature adjusted mid-wavelength infrared (MWIR) camera. Heat accumulation was triggered by simple yet effective temporal and geometrical restrictions of heat dissipation. This was realized by a variation of inter layer times and reduced cross section areas of the specimens. Differences in surface temperature of up to 800 K were measured. A severe development of keyhole porosity resulted from these distinct intrinsic preheating temperatures, revealing a shift of the process window towards unstable melting conditions. The presented results may serve as a warning to not solely rely on process parameter optimization without considering the actual process conditions a real component is faced with during the manufacturing process. Additionally, it motivates the development of representative test specimens.