Euro PM2024 Proceedings

Authors:

Alexander Holzer (1), Peter Nahringbauer (1), Lukas Stark (1), Christian Gierl Mayer (1)

1- TU Wien, Institute of Chemical Technologies and Analytics, Austria

Abstract:

Due to the strong dependency on powder supplier, additive manufacturing is restricted to a small range of materials and connected to big orders. Competitive and profitable production often requires serial production and therefore small products. The powder preparation, starting by producing the desired material composition, allows to design customized powder specialised for each additive application. In our case, ultrasonic atomization realizes batch-wise material research and prevents waste of material. In this work, opportunities and difficulties of the wire-fed ultrasonic atomization process is discussed. The main focus are stainless steels, e.g. 316L and variants, for lithography-based metal manufacturing. Furthermore, the powder characterisation, the tools for adjusting the powder atomization and first steps of additive manufacturing are presented. Results show that ultrasonic atomization provides narrow powder size distribution, almost perfect rounded powder without any satellites.

DOI:

https://doi.org/10.59499/EP246279391

Authors:

Mathias Moser (1), Mostapha Ariane (2), Laurent Buisson (3), Rémi Augustin (4), Pierre Sallot (4), Frédéric Bernard (1)

1- ICB UMR 6303 CNRS / uB, Dijon, France

2- SINTERMAT SAS, Venarey-les-Laumes, France

3- SATT Sayens, Dijon, France

4- SAFRAN TECH, Magny-Les-Hameaux, France

Abstract:

Spark Plasma Sintering technology is widely used to develop new materials with a fine and controlled microstructure. The key stage in its development (i.e. industrialisation) is the mastering of scale-up. From a SPS perspective, this requires suitable graphite tooling and a sintering cycle that can be applied to large parts. Samples with 60 mm diameter and 10 mm height were sintered from an aluminium alloy powder and characterised to determine the sintering conditions. Then, samples with 170 mm diameter and 15 mm height were sintered. Their metallurgical characterisations, including the numerical simulations of the sintering process, were performed to determine the effects of the scale-up and, at the end, to optimize the sintering conditions to obtain dense and homogeneous samples.

DOI:

https://doi.org/10.59499/EP246281373

Authors:

María Azpeleta (1), Piera Alvarez (1), Igor Ortiz (1), Asier Arizmendiarrieta (1), Diego Montoya-Zapata (1)

1- Ikergune A.I.E., INZU Group, San Antolin, 3, 20870 Elgoibar, Spain

Abstract:

In the context of large-scale parts manufacturing with laser cladding technology, the quality of the raw material conditions the quality of the coatings produced using this technology. The existing literature lists the different quality problems that occur in the process of laser cladding technology or focuses on the characterization of the powder feedstock. However, the relationship between the quality of the powder metal and the final properties of the manufactured parts has been poorly studied. Moreover, there is a need of defining permissible ranges of the measured variables (e.g., porosity and N content) that guarantee high quality parts. As a response to such a shortcoming, in this paper, we study the influence of the porosity of Stellite 6 powder on the microstructure and wear properties of laser cladding coatings. We compare two batches from two different suppliers with a noticeable difference in porosity level. We manufactured 3 prisms with each batch under the same processing conditions. The results of our experiments show that the powder with a higher level of porosity generates coatings with higher levels of porosity. These results demonstrate that the porosity of the raw material influences the quality, microstructure, mechanical performance and wear properties of the final part. These results also emphasize the need for common quality standards on the powder feedstock produced by different suppliers.

DOI:

https://doi.org/10.59499/EP246274806

Authors:

Adrien Delagnes (1,3), Clémence Hamann (1), Olivier Taché (2), Jacques Perrin Toinin (1), Brigitte Bacroix (3), Yann de Carlan (1)

1- Université Paris-Saclay, CEA, Service de Recherche en Matériaux et procédés Avancés, Gif-sur-Yvette, France

2- Université Paris-Saclay, CEA-CNRS (UMR 3685), Nanosciences et Innovation pour les Matériaux, la Biomédecine et l’Énergie, Gif-sur-Yvette, France

3- CNRS, Université Sorbonne Paris Nord, Laboratoire des Sciences des Procédés et des Matériaux, LSPM-CNRS (UPR 3407), Villetaneuse, France

Abstract:

Nickel-based alloys are attractive materials for the nuclear industry and in particular for Molten Salt Reactors (MSR). They are especially considered for neutron reflectors or heat exchangers. These alloys have many advantages, such as high mechanical properties at high temperature, and good corrosion resistance in chloride salt. A new nuance for MSRs is being developed at CEA. This alloy is obtained after consolidation by SPS and/or by HIP treatment of powders obtained by atomization. To resist irradiation, it is necessary to carefully control the nanoprecipitation in the material. This paper aims to show that the use of different characterization techniques, and in particular Small Angle X-rays Scattering (SAXS), makes it possible to specify the thermo-mechanical treatments, suggested to obtain the desired state of precipitation in this new alloy.

DOI:

https://doi.org/10.59499/EP246281783

Authors:

Curti Pier Paolo (1), Ariza Enrique (1), Neubauer Erich (1), Scheerer Michael (2), Stelzer Nils (2), Bača Ľubos (2)

1- RHP Technology, Austria

2- Advanced Aerospace and Composites, Austria

Abstract:

Nickel superalloys due to their good thermal mechanical properties and corrosion resistance are widely used for high performance on high demanding applications and industries as space, aviation or (petro-) chemistry. Moreover, the processing of this material class is costly due to the raw material and problems related to traditional processing techniques as casting, forging, or milling (hot cracking, porosity, work hardening or wear on milling tools). Within this study the alloy Inconel 718 is processed with Plasma Metal Deposition (PMD®), an additive manufacturing process with high deposition rates for large part production. Additionally, the alloy is reinforced with ceramic particles to improve the mechanical properties at high temperatures. The weldability is studied. To assess the performance test coupons are investigated and analysed with respect to the mechanical properties.

DOI:

https://doi.org/10.59499/EP246281339

Authors:

Thuli Mkhaliphi (1), Thorsten Becker (2), Xola Madyibi (1), Louis Louw (2)

1- Department of Industrial Engineering, Stellenbosch University, South Africa

2- Centre for Materials Engineering, University of Cape Town, South Africa

Abstract:

The study investigated the effect of the laser scanning strategy on the microstructural and material properties of the Ti-4.7Mo-4.5Fe alloy produced using laser powder bed fusion through in-situ alloying. The four scanning strategies used for the study were meander rotated at 45°, bi-directional alternating and rotated at 45° and 67° (Bi-45° and Bi-67°) and the Island. Cylindrical samples and tensile specimens, printed horizontally, were produced to investigate the microstructural and mechanical properties of the material, respectively. The study highlights and discusses the correlation between the amount of porosity, partially melted molybdenum, density, grain refinement, and the scanning strategies. The micro-hardness of the samples ranged between 451 and 484 HV with a minimum ultimate tensile strength (UTS) of 1000 MPa and minimum elongation% of 8%. The results showed that the Bi-45° and the Island laser scanning strategies are better suited for producing Ti-4.7Mo-4.5Fe alloy.

DOI:

https://doi.org/10.59499/EP246282627

Authors:

Ali N. Alagha (1), Emilio Galindo (1), Mathilde Rossier (1,2), Martin Conlon (3), José Muñiz (3), Kamran Azari (3), Evan Butler-Jones (3), Mathieu Brochu (1)

1-Department of Mining and Materials Engineering, McGill University, Montreal, Canada

2-University of Applied Sciences and Arts Western Switzerland, Sion, Switzerland

3-Equispheres Inc., Ottawa, Canada

Abstract:

In powder bed additive manufacturing processes, factors like moisture, oxidation, and surface contamination can impact powder cohesion leading to flow behavior degradation and ultimately part quality-related issues. Unfortunately, most of the existing powder characterization tools are either time-consuming/expensive to run or lack required sensitivity to precisely assess variations in powder surface conditions. Triboelectric charging, a phenomenon resulting from the contact and separation of materials, has recently gained attention as a method allowing differentiation of powder surface composition. Triboelectric charging is highly influenced by several powder characteristics including particle size, morphology, and surface composition. The focus of this presentation is to highlight the effect of surface chemistry on the triboelectric charging behavior of various aluminum alloy powders. This presentation will show the links between tribocharging response of various powders and their X-ray photoelectron spectroscopy (XPS) signature, to demonstrate how triboelectric charging can be used as a quick method to characterize powder surfaces.

DOI:

https://doi.org/10.59499/EP246281050

Authors:

Axel Müller-Köhn (1), Michael Hering (2), Johannes Abel (1), Darius Jucan (3), Stefan Jegust (4), Johannes Pötschke (1), Tassilo Moritz (1)

1- Institute for Ceramic Technologies and Systems, IKTS, Germany

2- Konrad Friedrichs GmbH & Co KG, Germany

3- Gühring Gühring SRL, Romania

4- INMATEC Technologies GmbH, Germany

Abstract:

Additive manufacturing allows machining tools to be specifically adapted to the machining task. However, currently the question remains whether additive manufactured hardmetal tools can achieve comparable performance to conventional produced hardmetal tools. In this study, hardmetal inserts manufactured using fused filament fabrication were tested in industrial machining trials on samples of AISI 304 (X5CrNi18-10). Due to their high degree of standardization and simple geometry, indexable inserts are well suited for such feasibility tests, although they do not have a geometry that requires or is advantageous for additive manufacturing. Within the presentation the whole process chain will be shown. Starting from powder, over the preparation of thermoplastic based filaments, the FFF printing up to the grinded tool. Specific issues for ensuring high material and component quality are discussed and an outlook into the use of ultrafine hardmetal powders more complex tools will be given. The promising results show great potential for complex special hardmetal tools, weight savings and conformal cooling.

DOI:

https://doi.org/10.59499/EP246281388

Authors:

Markus Schneider (1), Dennis Wawoczny (1, Kevin Haffke (1)

1- GKN Powder Metallurgy Engineering GmbH, Radevormwald, Germany

Abstract:

Ceramics and intermetallic compounds, e.g. sintered Nd2Fe14B hard magnets, are hard and brittle. The lack of any macroscopic plasticity yields to the fact that all defects exhibit its sharpest effect as predicted with the methods of the classical Linear Elastic Fracture Mechanics (LEFM) and Neuber’s theory of notch stresses. Residual stresses from the processing do not relax. The lack of any peak stress or stress intensity reducing plasticity explains its stronger scattering and Probability Density Function’s (PDF) loss of symmetry. The PDF of common ceramics are skewed and broader which leads to the need to consider the whole PDF and to define local component strength values. This refers to Weibull’s “weakest link theory”. Two different Nd2Fe14B hard magnet grades were tested and corresponding characteristic strength values and Weibull moduli were derived. The Weibull moduli can be used to predict the “size effect” or “volume effect” of the strength.

DOI:

https://doi.org/10.59499/EP246319979

Authors:

Damien Sicard (1,2), Mostapha Ariane (2), Frédéric Bernard (1), Foad Naimi (2)

1- ICB, UMR 6303 CNRS/Université de Bourgogne, Dijon, France

2- SINTERMAT SAS, Venarey Les Laumes, France

Abstract:

Over the last two decades, Spark Plasma Sintering (SPS) has become a major technique for manufacturing advanced materials. Nevertheless, the control of SPS process is complex and requires the use of complex multiphysics and multiscale numerical simulations. Nowadays, the emerging data-driven approaches such as Deep Learning (DL) have proven their effectiveness in many fields. Thus, we develop a DL architecture based on Convolutional Neural Network (CNN) and Generative Adversial Neural Network (GAN). The network is trained on high-throughput macroscale FEM simulation maps and associated process parameter tabular data. The power of this approach lies in the ability of the network training process to be incrementally augmented by multivariate data such as real microstructure images and real sintering signals: toward a SPS digital twin.

DOI:

https://doi.org/10.59499/EP246281353

Authors:

Pelle Mellin (1), Hanna Nilsson Åhman (1), Tatiana Fedina (1)

1- Swerim, Sweden

Abstract:

Concerns regarding the health implications of fine metal powder handling remain unresolved. Existing regulations such as occupational exposure limits are too blunt and do not guarantee safety in working environments. To better understand the health impact, airborne particles were captured in several PBF - LB workshops. Most 0-10 µm powder particles, which are considered respirable, are typically removed from as-atomized powders before being sold as PBF-LB powders. Yet, airborne 0-10 µm powder particles were found in all workshops. For cytotoxicity tests, we extracted the 0-10 µm powder particles using an AC1000G screenless air classifier from Blue Power. Furthermore, their size and physio-chemical characteristics were correlated with metal release in artificial lysosomal fluid (ALF). Results revealed a notable difference between the whole PBF-LB fraction and extracted 0-10 µm particles. No cytotoxicity was noted.

DOI:

https://doi.org/10.59499/EP246281401

Authors:

Hossein Eskandari Sabzi (1,2), Andrew Hamilton (2), Xinjiang Hao (1), Pedro E.J. Rivera-Díaz-del-Castillo (2)

1- Globus Metal Powders, United Kingdom

2- University of Southampton, United Kingdom

Abstract:

There are significant challenges in the additive manufacturing (AM) of high-performance steels susceptible to transformation-induced plasticity (TRIP) effect. This is a mechanically-induced martensitic transformation of retained austenite distributed in a ferritic or martensitic matrix. Austenite stabilisation and retention at room temperature is of paramount significance to promote TRIP. It was discovered that austenite could be effectively retained due to carbide precipitation during AM. The ultimate tensile strength then increases significantly as a result of this metastable austenite's gradual transformation into ε-martensite under straining, while exhibiting a high yield strength. The partitioning of stress and strain, which is constantly changing as the hard martensite forms, is the cause of this rise, as revealed by microscopy techniques and X-ray diffraction.

DOI:

https://doi.org/10.59499/EP246228829