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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:

S Venkatesh Kumaran (IMDEA Materials and Universidad Carlos III de Madrid, Spain), José Manuel Torralba (Universidad de Carlos III de Madrid and IMDEA Materials, Spain)

Abstract:

High entropy alloys (HEAs) have garnered significant research attention due to their unconventional alloying approach which results in exceptional properties. Recently, additive manufacturing processes like Selective Laser Melting (SLM) have been used to fabricate HEAs with enhanced mechanical properties. However, SLM processes demand the use of fully pre-alloyed powders since using elemental powders directly might lead to pronounced segregations. However, there are no readymade pre-alloyed HEA powders in the market and pure elemental powders are expensive. So, in this work, commercial commodity powders like Ni 625,CoCrF75, 316L, Invar36, and Fe49Ni which are readily available at competitive prices, were used to make HEAs. The selected powders were mixed in appropriate proportions and printed using SLM. The resultant alloy was a CoCrFeNiMox, with an FCC phase and exhibited promising mechanical properties. This work opens a completely new field of work with multiple possibilities to manufacture HEAs by additive manufacturing at competitive prices.

DOI:

https://doi.org/10.59499/WP225371709

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:

Aurelien Etiemble (Université de Lyon, ECAM Lasalle, France), Thierry Commeau (Umicore Specialty Powders France, France), Sandra Simon (Université de Lyon, ECAM Lasalle, France), Claire Rigollet (Université de Lyon, ECAM Lasalle, France)

Abstract:

The applicability and expansion of the promising opportunities offered by extrusion-based technologies for the additive manufacture of metal parts (FFF, FDM or PIM-like) depends on the development of new feedstock for specialty powders. In this context, W-based feedstock was developed and characterized in this study. For these indirect processes, the feedstock is firstly extruded to form a wire and is then deposited to shape the part. Debinding and sintering operations are finally required to obtain the finished metal part. The feedstock formulation was optimized to allow and then to enhance the processability at all these steps. The printability of W-based feedstocks is demonstrated and a critical powder content, required to guarantee the efficient debinding and sintering, is established. Microstructure and mechanical properties (hardness) of sintered parts were characterized and compared to conventionally manufactured parts.

DOI:

https://doi.org/10.59499/WP225371433

Authors:

Elena De Lamo (Universidad Castilla La Mancha, Spain) Ines Duran (Universidad Castilla La Mancha, Spain) Javier Hidalgo (Universidad Castilla La Mancha, Spain) Raquel Gimenez (Universidad Castilla La Mancha, Spain) Cristina Berges (Universidad Castilla La Mancha, Spain) Roberto Campana (Centro Nacional del Hidrógeno, Spain) Cristina García (Universidad de Valladolid, Spain) Gemma Herranz (Universidad Castilla La Mancha, Spain)

Abstract:

This study presents the design and validation of novel master alloy for powder injection moulding (PIM) and material extrusion (MEX) additive manufacturing of interconnectors for SOFC and SOEC systems. Using Crofer30 as a baseline, alloys with varying cobalt, manganese, and copper contents were developed to optimize thermal expansion, oxidation resistance, and mechanical strength. Feedstock formulations enabled defect-free interconnectors in pellet form for PIM and MEX. Sintering at 1320 °C achieved near-full densification with dispersed precipitates, enhancing hardness compared to Crofer30. Performance was evaluated through oxidation and hydrogenation tests across different temperatures, with microstructural and electrochemical analyses confirming improved corrosion and oxidation resistance. These advancements address current manufacturing challenges, supporting the development of efficient, durable, and cost-effective SOFC|SOEC interconnectors, and significantly advancing green energy technologies.

DOI:

https://doi.org/10.59499/EP256768199

Authors:

Yasin Mohamed El Sayed (RINA, Italy) Alessandro Colaneri (RINA, Italy) Stefano Lionetti (RINA, Italy) Oriana Tassa (RINA, Italy) Domenico Stocchi (ECOR, Italy) Luca Mengoli (ECOR, Italy) Mario Franchi (ECOR, Italy)

Abstract:

This study presents the development of two novel AlSi7Mg-based alloys tailored for additive manufacturing applications. The research was driven by a computational modeling approach to optimize the alloy composition and predict material behavior during processing. Following the modeling phase, gas atomization was employed to produce the alloy powders, ensuring suitable characteristics for powder bed fusion additive manufacturing (PBF-AM). Specimens were fabricated via PBF-AM to assess the printability and mechanical performance of the developed alloys. Comprehensive mechanical characterization (tensile testing, hardness measurements, and microstructural analysis), was conducted to evaluate the alloys performance. Results indicate that the newly developed AlSi7Mg-based alloys demonstrate improved mechanical properties and compatibility with AM processes compared to conventional AlSi7Mg. These findings contribute to the advancement of materials engineering for additive manufacturing, offering enhanced options for lightweight and high-performance applications.UNCLASSIFIED – Based on the Foreground Information under EDA contract No B.PRJ.RT.797 covering the Ad Hoc Project entitled AMALIA

DOI:

https://doi.org/10.59499/EP256767873

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:

Oliver Bürgi (IWM at RWTH Aachen University, Germany) Michael Norda (Fraunhofer IFAM, Germany) Anke Kaletsch (IWM at RWTH Aachen University, Germany) Christoph Broeckmann (IWM at RWTH Aachen University, Germany)

Abstract:

Laser beam powder bed fusion of metals (PBF-LB|M) provides exceptional geometric freedom, but the variety of processable materials remains limited. In particular, the precise control of specific microstructures, like coarse carbides for better resistance against abrasive wear, continues to present challenges in research. In this study, hot work tool steel powder was mixed with high-speed steel (HSS) powder and titanium carbides (TiC) to develop an in-situ alloyed carbide-rich cold work tool steel.Thermodynamic calculations were performed to design an alloy system leading to a promising microstructure. During processing, TiC partially dissolved, resulting in coarse undissolved carbides and reprecipitated primary carbides. Carbide-forming elements like molybdenum (Mo), vanadium (V) and tungsten (W) are added as HSS powder to enhance the alloy´s potential for secondary hardening. The influence of PBF-LB|M process parameters on resulting carbides were analysed. In-depth microstructure analyses were conducted using scanning electron microscopy (SEM) and electron backscatter diffraction (EBSD).

DOI:

https://doi.org/10.59499/EP256766986

Authors:

Lea Reineke (Fraunhofer IFAM, Germany) Alena Clausen (Fraunhofer IFAM, Germany) Regina Schlegel (Fraunhofer IFAM, Germany) Malte Sandmann (Fraunhofer IFAM, Germany) Sebastian Boris Hein (Fraunhofer IFAM, Germany)

Abstract:

The development of a curing-free binder system for reactive materials in Metal Binder Jetting (MBJ) aims to simplify the process chain and enhance the possibilities of MBJ technology. Traditional binder systems need a curing step that involve temperature treatment, which can have a negative impact on oxygen and water-reactive powders. This study introduces a new binder system that eliminates the need for curing, enabling the use of reactive powders without temperature influence. By removing the curing step, the proposed system not only shortens the overall MBJ process but also expands the range of materials that can be used in Metal Binder Jetting. The results demonstrate the feasibility of working with sensitive materials while maintaining the integrity and performance of the final part. This innovation paves the way for more efficient, adaptable, and material-diverse applications in additive manufacturing.

DOI:

https://doi.org/10.59499/EP256764448

Authors:

Michael Norda (1), Jan Henrik Lübbe (1), Prof. Dr. Frank Petzoldt (1), Prof. Dr. Ralf M. Gläbe (2)

1- Fraunhofer Institute for Manufacturing Technology and Advanced Materials IFAM, Wiener Straße 12, 28359 Bremen, Germany

2- HSB Hochschule Bremen - City University of Applied Sciences, Neustadtswall 30, 28199 Bremen, Germany

Abstract:

The metal binder jetting (MBJ) process is a powder bed-based Additive Manufacturing (AM) process, which is attracting growing interest. In this process, a liquid binder deposited by a print head bonds the powder particles to create so-called green parts. For a reliable metal binder jetting process, the metal powder must have a high quality. The morphology and particle size distribution have a major influence on the flowability and sinterability of the material. In this work, the aging process is observed particularly regarding the slightly disappearing fine fraction during the process. A practical method is presented to reliably detect the ageing process of the powder. In addition, a method is developed to stop or curb ageing to support constant printing conditions. The experiments are conducted using 17-4PH stainless steel. Several properties of powders and parts are analysed such as particle size distribution, green part density, powder bed density and dimensional tolerances.

DOI:

https://doi.org/10.59499/EP246246174

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