Authors:
Paul Calves (Centre Technique des Industries Mécaniques (CETIM), France), Maxime Robert (Centre Technique des Industries Mécaniques (CETIM), France), Corentin Carree (Centre Technique des Industries Mécaniques (CETIM), France)
Abstract:
Today, the building rates with Metal Binder Jetting technologies start to reach very high rates, giving good perspectives for mass production. But one remaining challenge is also to master the dimensional dispersion in production, and to guarantee an Interval of Tolerance satisfying industrial specifications and needs.This presentation will detail in a first part, the progression towards a reliable and efficient method allowing to evaluate the dimensional dispersion of Metal Binder Jetting machines.Then several results and observations, among other the Interval of Tolerance depending on some printing parameters and observables as green and as sintered, will be presented and discussed.
DOI:
https://doi.org/10.59499/WP225370845
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Authors:
Louise Toualbi (ONERA, France), Yann Le Bouar (ONERA, France), Jean-Sébastien Mérot (ONERA, France), Federico Orlacchio (ONERA, France), Pauline Stricot (ONERA, France), Agnès Bahcelier-Locq (ONERA, France), Nicolas Horezan (ONERA, France), Denis Boivin (ONERA, France), Cécile Davoine (ONERA, France), Marc Thomas (ONERA, France)
Abstract:
The L-PBF process features very short interactions between the powder and the laser, resulting in very high solidification and cooling rates. During thermal cycling in L-PBF processing, phase precipitation and thermal strain hardening occur concomitantly, thus leading to high dislocation density correlated with anchoring to precipitates. It is therefore important to understand and control precipitation kinetics with respect to the thermal strain hardening phenomena generated by the thermal cycles of the L-PBF process. This issue concerns structural hardening aluminium alloys.The aim of this study is to understand the thermal, metallurgical and mechanical phenomena generated during the manufacture of a model aluminium alloy (Al-4Fe) by L-PFB, in order to evaluate the impact of thermal strain hardening on the precipitation of the strengthening phases. A fine microstructural characterization using scanning electron microscopy and transmission electron microscopy shows a strong the interaction between dislocation density and precipitation.
DOI:
https://doi.org/10.59499/WP225371451
Authors:
IrmaHeikkilä (1), Oliwer Gustavsson (1), Oskar Karlsson (1), Cameron Blackwell (2), Aneta Chroztek-Mroz (2), Laurent Pambaguian (3), Martina Meisnar (3)
1- Swerim AB, Sweden
2- MTC Ltd., UK
3- ESA, UK
Abstract:
The mechanical strength of laser powder bed fusion (L-PBF) of AlSi10Mg is correlated to a fine hierarchical microstructure formed during the repeated layer-by-layer melting guided by a digital model. The microstructure of the surface area of the L-PBF parts is often different to that of the bulk material as specific laser contouring strategies are applied at the surface areas. However, the evaluation of the mechanical strength is frequently made on machined tensile specimens where the microstructure of the surface area is removed. In this investigation, two different AlSi10Mg powders are processed by two bureaus, each having different contouring strategies. Mechanical testing is conducted with machined and contoured specimens. The microstructure and fracture surfaces of four materials is studied, both in un-treated and annealed conditions. The results show that the mechanical strength of the contoured specimens is slightly lower than the one of the machined specimens and has a correlation to the microstructure at the contour areas.
DOI:
https://doi.org/10.59499/EP246282705
Authors:
Julian Henrichs (1,2), Jimmy Hilbert (1), Ronald Rosenberg (2), Pierre Forêt (2), Marcus Giglmaier (1), Nikolaus A. Adams (1)
1- Technical University of Munich; TUM School of Engineering and Design, Chair of Aerodynamics and Fluid Mechanics, Boltzmannstr. 15, D-85748 Garching, Germany
2- Linde GmbH, Linde Technology - Additive Manufacturing, Carl-von-Linde-Straße 25, D-85716 Unterschleißheim, Germany Abstract
Abstract:
One of the current major barriers to the industrialization of metal additive manufacturing (AM) is the cost-effective production of a high-quality metal powder, usually in the range of 1-150 μm, making investigations of the atomization process essential. Numerical investigations usually reach their limits due to the massive multiscale problem, whereas experimental investigations are either performed on a laboratory scale with limited transferability or on industrial equipment with limited accessibility for measurement techniques. To face this challenge a new atomization test bench (ATB) is developed which was tailored for detailed experimental investigation on the fundamentals of atomization in an industrial scale set-up. All input parameters can be set individually and are measured continuously and precisely. At the same time, the good optical accessibility allows a temporally and spatially highly resolved visualization of the gas flow as well as a detailed investigation of the mechanisms of decomposition during primary and secondary atomization.
DOI:
https://doi.org/10.59499/EP235768771
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Authors:
Sohret Melda Aydin (EGE University, Turkey), Tugçe Tekin (EGE University, Turkey)
Abstract:
Commercial purity Mg powders were sintered at 300°C for 15 minutes with alternating current electric field-assisted sintering technique (FAST) under the pressure of 30 MPa after mechanical milling for 4-8-12-16-20 hours. Powder geometries, sizes and microstructural properties of the powders were investigated depending on the milling time. The relationship between the pore ratio and pore structure of the sintered samples and their powder geometries was investigated. Depending on the powder microstructure and geometry, the realization mechanism of FAST has been examined and evaluated with the results of compressive strength and hardness tests. The results were supported by optical microscope images, Scanning Electron Microscope (SEM) images. It has been determined that powder geometries (platy-spherical) -especially in the FAST method- have a great effect on sinterability and pore size, shape, and distribution.
DOI:
https://doi.org/10.59499/WP225370249
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Authors:
Fenja Habelmann (1,2), Saeed Khademzadeh (2), Arvid Svanberg (2), Anna Larsson (3), Seyed Behnam Hosseini (2)
1- University of Rostock, Germany
2- Department of Manufacturing Processes, RISE Research Institutes of Sweden, Mölndal, Sweden
3- Höganäs AB, Höganäs, Sweden
Abstract:
While laser powder bed fusion (PBF-LB) technology holds significant promise for integration into industrial manufacturing workflows, it still faces challenges related to low production rates. Adjusting process parameters, such as increasing layer thicknesses and scanning speeds, proves effective and cost-efficient in enhancing productivity in the PBF-LB process. However, ensuring the retention of appropriate properties poses challenges, which necessitate further studies. Another obstacle arises from the elevated energy input required to accommodate increased layer thicknesses, leading to a higher level of spatters. This study examines the feasibility of enhancing productivity in PBF-LB for IN718 components using this approach, encompassing both bulk samples and inclined features. The investigation includes various material responses, including relative density, surface roughness, microstructure, and spatter formation. Optimal process parameters have been determined for different layer thicknesses, extending up to 120 μm, with corresponding adjustments tailored for downfacing surfaces.
DOI:
https://doi.org/10.59499/EP246281718
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Authors:
Asier Lores (1), Iñigo Agote (1), Xabier Gomez (1), Unai Andrés (2)
1- TECNALIA, Basque Research and Technology Alliance (BRTA) Donostia/San Sebastian, Spain
2- ALFA MIMTech Alfa S.L., Eibar, Spain
Abstract:
Many requirements and applications in various industrial sectors demand high-quality finishes on parts. These finishes, whether due to tolerances or surface quality, are often challenging to achieve through additive manufacturing technologies, necessitating additional post-processing. This study aims to investigate the effect of specific surface treatments on parts produced through Sintering Based Additive Manufacturing (SBAM), such as Fused Filament Fabrication (FFF). With the premise of employing affordable post-processing methods that can potentially maintain competitive prices for the parts, the study analyzes the post-processing techniques of shot blasting and vibratory polishing on parts with different geometries. Additionally, the study examines the effect of surface treatments on part walls manufactured at various angles. The results obtained demonstrate significant improvements in surface roughness, although there is potential for them to modify the geometry and round the edges of the parts.
DOI:
https://doi.org/10.59499/EP246283231
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Authors:
Rafik Safar Bati (Univ. Grenoble Alpes, France), Marco Zago (Univ. Grenoble Alpes, France), Jean-Michel Missiaen (Univ. Grenoble Alpes, France), Didier Bouvard (Université Grenoble Alpes, France), Jean-Marc Chaix (Univ. Grenoble Alpes, France), Faisal Balarabe (Univ. Grenoble Alpes, France), Yvan Avenas (Univ. Grenoble Alpes, France)
Abstract:
The interest of composite extrusion modelling (CEM) for additive manufacturing of metal components is growing up due to the low cost of this process and to the possibility of using commercial MIM feedstock. In a previous study, the successive stages of the processing route of simple copper parts have been optimised with regard to the final weight density and surface roughness. The next step has consisted in fabricating components with controlled porous architecture, to be used for cooling power electronic chips with an air flow. The thermo-hydraulic properties of these components (thermal resistance, air pressure drop) have next been measured. For future practical application of this heat sink, its bonding to a copper plate has been ensured by printing the feedstock directly upon the plate and next sintering the assembly. The shear resistance of this bonding has been found to be in line with power electronics standards.
DOI:
https://doi.org/10.59499/WP225367584
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Authors:
Fernanda Signor (1), Maria José Silva Carvalho (1), Augusto Botton Pozzebon (1), William Bevilaqua (2), Inacio Limberger (1), Natália de Freitas Daudt (1,3)
1- Grupo de Tecnologia e Mecânica dos Materiais (GMAT), Departamento de Engenharia Mecânica, Universidade Federal de Santa Maria, Brazil
2- Colégio Técnico Industrial de Santa Maria (CTISM), Universidade Federal de Santa Maria, Brazil
3- Mechanical Engineering Post-Graduate Program (PGMEC), Departamento de Engenharia Mecânica, Universidade Federal de Santa Maria, Brazil
Abstract:
The fabrication of copper parts by 3D-extrusion of highly viscous paste was studied. This technology is classified as sinter-based AM technology. Extrusion-based 3D printing have been often reported in literature for production of ceramics components, however there are still few studies on metal components. 3D-extrusion allows printing of metallic components with a low anisotropy index, by deposition of layers of a paste composed of polymeric solution loaded with metal powder. In the present study, we evaluated the effect of paste composition on the microstructure and compressive strength behavior of copper parts. For that three different composition of water based polymeric pastes loaded with copper particles were prepared. Green parts were printed by paste extrusion at room temperature. Afterwards the parts were debinded and sintered. Extrusion-based 3D printing of metals pastes is an attractive route for cost effective production of small batches of complex shaped parts.
DOI:
https://doi.org/10.59499/EP235764456
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Authors:
G. Miranda (1), L. Basílio (2,3), B. Guimarães (2,3), O. Carvalho (2,3), C. M. Fernandes (4), D. Figueiredo (4), F. S. Silva (2,3)
1- CICECO - Aveiro Institute of Materials, Department of Materials and Ceramic Engineering, University of Aveiro, 3810-193 Aveiro, Portugal
2- Center for MicroElectroMechanical Systems (CMEMS-UMinho), University of Minho, Campus de Azurém, 4800-058 Guimarães, Portugal
3- LABBELS – Associate Laboratory, Braga/Guimarães, Portugal
4- Palbit S.A., P.O. Box 4, 3854-908 Branca, Portugal
Abstract:
Laser surface texturing has a high potential for the development of innovative solutions for the cutting tool industry, by allowing the fabrication of high-precision micro-scale geometries. In this study, different cross-hatched micro patterns were explored, by using an Nd:YAG laser to texture WC-10wt% Co green compacts. After dewaxing and sintering, a complete characterization was performed to evaluate topography, roughness, and dimensions of the fabricated textures. This study allowed to conclude on the better scanning strategy and laser parameters for obtaining a given texture geometry with defined dimensions on a reproducible manner. Besides allowing to modify a selected surface area, targeting to higher wettability or increased contact area, this approach has shown not to compromise the integrity and mechanical strength of the compact, allowing to preserve the tool conventional functionality.
DOI:
https://doi.org/10.59499/EP235765405
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Authors:
Koki Nakamura (Toyohashi University of Technology, Japan), Atsushi Yokoi (Toyohashi University of Technology, Japan), Go Kawamura (Toyohashi University of Technology, Japan), Atsunori Matsuda (Toyohashi University of Technology, Japan), Hiroyuki Muto (Toyohashi University of Technology, Japan)
Abstract:
In nanocomposite materials fabrication, nanopowders are commonly used to obtain the desired properties. However, the drawbacks of nanopowders are agglomeration and poor handling ability. To overcome these issues, one solution is to fabricate composite granules using electrostatic integrated granulation of aqueous nanopowder suspension. By adjusting the surface charge potential of the nanopowders, electrostatic integration during the granulation process enabled the fabrication of monodispersed spherical composite granules, exhibiting good homogeneity of raw nanoparticles and improved handling ability. In this study, the parameters for composite granules formation using electrostatic integrated assembly method were investigated. From the results obtained, a process map, which enables the prediction of the granule’s formation is also proposed.
DOI:
https://doi.org/10.59499/WP225371880
Authors:
Gee Hyuk Lee (Korea Institute of Industrial Technology (Korea National Institute of Rare Metals, Incheon, Republic of Korea), Inha University, Korea, Republic of) Yong Kwan Lee (Korea Institute of Industrial Technology (Korea National Institute of Rare Metals, Incheon, Republic of Korea), Korea University, Korea, Republic of) Yong Yeon You (Korea Institute of Industrial Technology (Korea National Institute of Rare Metals, Incheon, Republic of Korea), Korea University, Korea, Republic of) Seok Jun Seo (Korea Institute of Industrial Technology (Korea National Institute of Rare Metals, Incheon, Republic of Korea), Korea, Republic of) Jae Jin Sim (Korea Institute of Industrial Technology (Korea National Institute of Rare Metals, Incheon, Republic of Korea), Korea, Republic of)
Abstract:
Nickel nanopowders, known for their excellent electrical conductivity and oxidation resistance, are essential in industries such as electronics and energy storage. As internal electrode materials in MLCCs (multilayer ceramic capacitors), they play a key role in achieving high capacity and miniaturization. Conventional processes like PVD and CVD produce high-purity nickel powders but face challenges such as broad particle size distribution and high production costs. Wet chemistry offers a cost-effective and efficient alternative, enabling precise particle size control and reduced agglomeration. This study optimized key process variables, including reducing agents, additives, and precursor concentrations, to evaluate their effects on particle size, purity, and carbon content. The synthesized nanopowders were characterized using SEM, PSA, XRD, and ICP-OES. Results confirmed the feasibility of producing high-purity and low-carbon nickel nanopowders suitable for MLCC applications.
DOI:
https://doi.org/10.59499/EP256765921
