Euro PM2023 Proceedings

Authors:

Emma Gil (1); Raúl Gómez (1); Fermin Garciandia (1); Maria San Sebastian (1); Ane Miren Mancisidor (1)

1- LORTEK, Arranomendi Kalea 4A, 20240 Ordizia, Spain

Abstract:

CM247LC alloy is a precipitation strengthened nickel-based superalloy commonly used in aeronautic sector due to its outstanding mechanical, oxidation, creep and wear properties at room and at high temperatures. However, there is a big challenge in obtaining a crack free material during PBF-LB/M processing. High contents of Al and Ti induce cracking. Four batches of CM247LC powders with different compositions were analysed and processed by PBF-LB/M. In this study, different approaches were employed to mitigate crack susceptibility of the alloy, namely, alloy modification, process modification and post-processing by HIP. The influence of the elements on cracking was assessed as well as the process parameters modification, including modification of the laser scanning strategies. Microstructure before and after post-processing, namely heat treatments and HIPping, was evaluated and cracking mechanism was studied in the light of microstructural observations.

DOI:

https://doi.org/10.59499/EP235762584

Authors:

Sandra Wieland (1); Lea Reineke (1); Julius Eckel (1); Jonathan Giel (1); Sebastian Boris Hein (1)

1- Fraunhofer IFAM, Wiener Straße 12, 28359 Bremen, Germany

Abstract:

Along the Metal Binder Jetting process chain, the metal powder is subjected to interactions with the binder, which is often water-based, and with air at elevated temperature during the curing step. This can lead to corrosion or oxidation reactions, especially for non-corrosion-resistant materials like typical tool steels. In order to investigate the interaction of non-corrosion resistant steels and different binders as well as the curing behaviour, two commonly used tool steels (PM-V10 and M2) are combined with three different binders. Measurements are carried out on the wetting behaviour of all powder-binder combinations, by determining the saturation rate and equilibrium binder saturation. Curing temperatures are set according to the respective binder composition, and both curing in air as well as in protective atmosphere is tested. The evaluation includes the shape of the resulting green parts and the density, microstructure, and carbon and oxygen content of parts after debinding and sintering.

DOI:

https://doi.org/10.59499/EP235764652

Autors; 

S. Fooladi Mahani (1); C. Liu (2); F. García-Marro (1,3); X.K. Cai (2); E.Jiménez-Piqué (1,3); L. Llanes (1,3)

1- CIEFMA, Department of Materials Science and Engineering, Universitat Politècnica de Catalunya - BarcelonaTech, Campus Diagonal Besòs-EEBE, Barcelona 08019, Spain

2- Xiamen Tungsten Co., Ltd., 361009 Xiamen, China

3- Barcelona Research Center in Multiscale Science and Engineering, Universitat Politècnica de Catalunya - BarcelonaTech, Campus Diagonal Besòs, 08019 Barcelona, Spain

Abstract:

Resistance to contact loading is a key issue to consider for microstructural design of cemented carbides to be used as tools and wear components. In this work, Vickers, conical and Hertzian indentation has been implemented to assess contact damage response for three microstructurally different WC-Co cemented carbides. Deformation and damage linked to induced imprints were inspected at both surface and subsurface levels, the latter through sequential tomography. Results are presented as damage maps as a function of applied load. It is found that critical load values for emergence of cracks as well as for their subsequent evolution are strongly dependent on indenter geometry (linked to specific stress field) and fracture toughness of the material. Practical implications of these findings, in terms of future damage tolerance studies, are finally discussed.

DOI:

https://doi.org/10.59499/EP235761011

Authors:

G. Poehle (1), P. Quadbeck (2), S. Riecker (1), C. Kukla (3), V. Momeni (4), S. Schuschnigg (4)

1- Fraunhofer Institute for Manufacturing Technology and Advanced Materials IFAM, Dresden, Germany

2- Offenburg University of Applied Sciences, Offenburg, Germany

3- Montanuniversitaet Leoben, Industrial Liaison Department, Leoben, Austria

4- Montanuniversitaet Leoben, Department of Polymer Engineering and Science, Institute of Polymer Processing, Leoben, Austria

Abstract:

Fused Filament Fabrication (FFF) is a widespread additive manufacturing technology, mostly in the field of printable polymers. The use of filaments filled with metal particles for the manufacture of metallic parts by FFF presents specific challenges regarding debinding and sintering. For aluminium and its alloys, the sintering temperature range overlaps with the temperature range of thermal decomposition of many commonly used “backbone” polymers, which provide stability to the green parts. Moreover, the high oxygen affinity of aluminium necessitates the use of special sintering regimes and alloying strategies. Therefore, it is challenging to achieve both low porosity and low levels of oxygen and carbon impurities at the same time. Feedstocks compatible with the special requirements of aluminium alloys were developed. We present results on the investigation of debinding/sintering regimes by Fourier Transform Infrared spectroscopy (FTIR) based In-Situ Process Gas Analysis and discuss optimized thermal treatment strategies for Al-based FFF.

DOI:

https://doi.org/10.59499/EP235764658

Authors:

M. A. Lagos (1); N. Azurmendi(1); A. Lores (1); I. Leizaola (1); I. Agote (1)

1- TECNALIA, Basque Research and Technology Alliance (BRTA), Mikeletegi Pasealekua 2, 20009 Donostia-San Sebastián, Spain

Abstract:

Binder Jetting is capable of cost-effectively producing complex metal and ceramic components without the need for support structures. However, printed parts typically contain porosity due to the use of coarse powders and a loosely packed powder bed. For some materials, it is difficult to achieve full density without infiltration of a secondary lower melting point material.

This work presents the post-densification of binder jetting parts by a pressure assisted sintering process, Spark Plasma Sintering. Sacrificial powder was used in other to maintain the complex geometry. Copper pieces were successfully densified using different starting conditions. However, densification of the pieces was not isotropic, and thus some design considerations are explained in order to obtain the right geometry. Additionally, considerations about the possible scalability and industrial application of this approach are also presented.

DOI:

https://doi.org/10.59499/EP235753924

Authors:

O. Utku Uçak (1), Marco Zago (1), Bruno Vicenzi (2), Mark James Dougan (3), Markus Schneider (4), Preben Hedegard Pedersen (5), Juergen Voglhuber (6), Ilaria Cristofolini (1)

1- University of Trento - Trento, Italy

2- EPMA, Chantilly - France

3- AMES Barcelona Sintering S.A., Barcelona – Spain

4- GKN Sintermetals GmbH, Radevormwald - Germany

5- Sintex a/s, Hobro - Denmark

6- Miba Sinter Austria GmbH, Vorchdorf - Austria

Abstract:

Design for Sintering 2 is an EPMA Club Project aimed at improving the previously developed design procedure accounting for anisotropic dimensional changes on sintering. Goal of the project is both enlarging the reference database through the fruitful cooperation of the industrial partners and investigating in depth the mechanisms responsible for anisotropic dimensional changes. This work is focused on the second part of the project, aimed at studying the influence of compaction parameters. Axi-symmetric parts characterized by different materials and geometrical parameters were produced at different green densities with different compaction strategies. Focusing the attention on the anisotropy in the compaction plane, dimensional changes were measured and evaluated, also relating them to the attainable dimensional tolerances. The influence of compaction strategy was analyzed in depth, and for the different materials and geometries the more robust process conditions for dimensional precision were highlighted.

DOI:

https://doi.org/10.59499/EP235765189

Authors:

Masari Facundo (1), Hernández Pascual Rebeca (2), Hernández Mayoral M. Mercedes (2), Torralba José Manuel (2,3), Campos Mónica (2)

1- Universidad Carlos III de Madrid, Leganés Madrid, Spain

2- Centre for Energy, Environmental and Technological Research (CIEMAT), Madrid, Spain

3- IMDEA Materials Institute, Getafe Madrid, Spain

Abstract:

Increasing the operating pressure and temperature of power plants is one method to increase their efficiency and hence lower CO2 emissions. The materials employed define the maximum operating parameters of a plant, ergo, it is crucial to develop new materials to raise its working conditions. Currently, alumina-forming austenitic steels), alloys vulnerable to stress corrosion cracking and irradiation swelling, are one of the materials used for temperatures about 750°C. A novel type of material is proposed, alumina-forming ferritic-martensitic steels, which have superior corrosion and swelling resistance. Advanced fabrication techniques like field-assisted sintering and selective laser melting are explored to achieve different microstructures, starting from pre-alloyed atomized powders. These microstructures were studied with SEM and EBSD, while their mechanical behaviour was observed at room temperature. Finally, corrosion tests were conducted at temperatures of 800°C for 500 hours.

DOI:

https://doi.org/10.59499/EP235765533

Authors:

A. Meza (1), A. Barbosa (2), X. Yang (1), E. Tabares (2), J.M. Torralba (1,2)

1- IMDEA Materials Institute, Eric Candel 2, 28906 Getafe, Spain

2- Universidad Carlos III de Madrid, Av. Universidad 30, 28911 Leganés, Madrid, Spain

Abstract:

High Entropy Alloys (HEAs) have increasingly attracted the scientific community’s attention due to their unique microstructures and mechanical performance. However, one of the HEAs’ main drawbacks to being developed by powder metallurgy is the need for prealloyed powders with the specific composition of the HEA, which increases the overall cost. Thus, in this work, commercial commodity powders like Ni625, CoCrF75, or 316L were employed to manufacture HEAs by Powder Injection Moulding (PIM). These powders were mixed with a multi-component binder to produce sustainable feedstocks using a combination of low CO2-emitting and water-soluble polymers. The critical solids content was determined, and the rheological properties, debinding conditions, and sintering parameters were adjusted to obtain samples with low porosity. In addition, all PIM stages were thoroughly characterized to control the porosity of the end parts and to ensure a single FCC solid solution with promising mechanical properties in the developed CoCrFeNiMox-type HEAs.

DOI:

https://doi.org/10.59499/EP235765012

Authors:

Rodolfo L. Batalha (1), Francisco Feliciano (1,2), Angelo Andreoli (3), Paulo J. Morais (1), Maria Margarida Cruz (4), Guiomar Evans (2)

1- ISQ - Instituto de Soldadura e Qualidade, Avenida Professor Dr. Cavaco Silva 33 Taguspark, 2740-120 Porto Salvo, Portugal

2- University of Lisbon, Campo Grande 016, 1749-016 Lisboa, Portugal

3- Federal University of São Carlos, Rod. Washington Luiz km 235, 13.565‑905 São Carlos, Brazil

4- BioISI, Faculty of Science, University of Lisbon, 1749-016 Lisboa, Portugal

Abstract:

Magnetic materials are becoming increasingly important due to the development of renewable energy sources. Soft magnetic components are used in electric machines such as motors, generators, inverters, converters, transformers, and sensors. In this work, we processed Fe-Si-based soft magnetic materials with powder bed fusion-laser beam (PBF-LB), additive manufacturing (AM) technology. The work considered the development of Fe-Si alloys by powder mixture, additive manufacturing of samples, post-processing heat treatments, and the measurement of magnetic properties. The results showed that the thermal history associated with the processing route leads to a notable change in the magnetic properties of the Fe-Si alloys. It is also seen that the microstructure and therefore magnetic properties of the Fe-Si alloy may be tailored by changing the laser scanning strategy in the PBF-LB process

DOI:

https://doi.org/10.59499/EP235764401

Authors:

Olaf Andersen (1), Cris Kostmann (1), Ralf Hauser (1), Franziska Gebauer (2), Steffen Schramm (2), Thomas Weißgärber (1,3)

1- Fraunhofer Institute for Manufacturing Technology and Advanced Materials IFAM, Branch Lab Dresden, Germany

2- Papiertechnische Stiftung PTS, Heidenau, Germany

3- Institute of Materials Science, Chair Powder Metallurgy, Technical University of Dresden, Germany

Abstract:

Using processes derived from paper technology, organic fibers, fillers, and additives can be mixed with metal powder to produce a flat product. In a subsequent heat treatment, the organic components are removed, leaving a purely porous metallic material, the so-called sinter paper. This approach is used for the development of an innovative Gas Diffusion Layer (GDL) for mobile fuel cells. GDLs are arranged between the bipolar plate and the electrode in fuel cell stacks. They ensure optimal gas distribution as well as the removal of water, heat, and electricity. Metallic sinter paper that meets the materials specification of stainless steel 316L could be made. The thickness of the paper was reduced to 200 µm, and the porosity of the base material reaches values around 60 %. Morphological characterization was carried out based on high-resolution µCT scans and their analysis via the software package GeoDict.

DOI:

https://doi.org/10.59499/EP235765639

Authors:

Dipl.-Ing. Susanne Mosler (1), Dr.-Ing. Kay Reuter (2)

1- Rolls-Royce Deutschland Ltd & Co KG, Germany

2- Fraunhofer Institute for Manufacturing Technology and Advanced Materials IFAM, Branch Lab Dresden, Germany

Abstract:

The aerospace industry has been relying on a limited range of options for air system sealing solutions and is now exploring improvement opportunities by using 3D screen printing technology. As a sinter-based metal powder process screen printing allows freedom in material choice as well as seal structure design. To achieve high sealing performance stringent requirements on uniformity and repeatability of component features have to be fulfilled. The influence of screen printing process parameters and sinter process parameters on material properties are investigated.

DOI:

https://doi.org/10.59499/EP235765437

Authors:

Valérian Iss (1), Alexander Ulferts (2), Ali Rajaei (1), Christoph Broeckmann (1)

1- Chair and Institute for Materials Applications in Mechanical Engineering, RWTH Aachen University, Germany

2- Inductoheat Europe, Inductotherm group, Germany

Abstract:

Induction hardening enables to control the properties of the surface layer of components through suitable process parameters. This heat-treatment is characterized by short process times, low energy costs, high reproducibility and low distortion levels. With sintered steels, however, the risk of cracking in induction hardened components is high due to low thermal conductivity, reduced ductility and high residual stresses [1]. Large scale deployment of induction hardening for sintered steel components requires deeper understanding of the relationships between material and process parameters. In this work, the relevant material data, such as the phase transformation behavior of different alloys, is determined. Induction hardening tests on components made of sintered steels are carried out with systematic variation of both material properties (carbon concentration, porosity) and process conditions (heating, quenching and tempering parameters), in order to link these interacting parameters with the resulting microstructure, hardness, residual stresses and susceptibility to cracking.

DOI:

https://doi.org/10.59499/EP235762567