Euro PM2023 Proceedings

Authors:

Vikner Peter (1), Egea Philippe (2), Michel Loic (2), Joffre Thomas (3), Garabedian Stephane (3), Langer Lukas (4), Legay Florence (2)

1-Aubert&Duval, Paris, France

2-Aubert&Duval, Les Ancizes, France

3-IPC, Bellignat, France

4-Fraunhofer IGCV, Augsburg, Germany

Abstract:

Stellar®X15TN (1.4123 / ASTM F899) is a nitrogen alloyed, cobalt free 0,4% C martensitic stainless steel which is easy to print by LPBF despite its relatively high carbon content. The steel combines a capability to be heat treated to over 58 HRC with an excellent corrosion resistance and a good polishability. Being magnetic and relatively soft in its as built and stress relieved state it is easy to machine, which is necessary for example for drilling and threading of fixation holes. The fact that it is cobalt free is another important feature due to health concerns. Therefore, Stellar® X15TN is suitable for additive manufacturing of plastic injection molds with conformal cooling, surgical tools, cutting tools for food and pharma processing but also for other components where a combination of high hardness and corrosion resistance is requested such as bearing and valve components. Nitrogen enhances the hardness and the wear resistance of the material through formation of carbonitrides. It is also an austenite stabilizing element that reduces the martensite start (Ms) and finish (Mf) temperatures which improves the printability. Finally, nitrogen has a positive impact on corrosion resistance. The challenge is to add nitrogen and to not lose it during the additive manufacturing. Previous studies have exposed the printing parameters. This work presents different heat treatments and their impact on the main usage properties such as hardness and impact strength..

DOI:

https://doi.org/10.59499/EP235746422

Authors:

Corina Junghetu (1), Chris Schade (2), Kerri Horvay (2), Tom Murphy (2)

1- Hoeganaes Corporation Europe, Romania

2- Hoeganaes Corporation, USA

Abstract:

Applications that require wear resistance use hard materials which are difficult to machine. The most common forming method is by grinding but that limits the part geometry that can be achieved. Using additive manufacturing to form parts will open the range of possible geometries and functionalities that have never been explored. In this study, the mechanical properties, microstructure, standardized wear testing and toughness were evaluated for as-built and heat-treated samples for a series of wear-resistant alloys developed to provide a range of properties for different tooling applications. The samples were prepared by printing with the laser powder bed fusion technique (LPBF) and then heat treated in different conditions.

DOI:

https://doi.org/10.59499/EP235760998

Authors:

Yannik Wilkens (1), Ebrahim Ghavampour (1, 2), Tim Lantzsch (3)

1- SMS group GmbH, Düsseldorf, Germany, yannik.wilkens@sms-group.com

2- RWTH Aachen University, Chair for Laser Technology LLT, Aachen, Germany

3- Fraunhofer Institute for Laser Technology ILT, Aachen, Germany

Abstract:

In powder-bed-based additive manufacturing (AM) processes, the flowability of the powder is decisive for the quality of the manufactured part. Since fine particle fractions worsen the flowability, in the laser powder bed fusion (LPBF) process the lower limit of the powder fraction is usually 15 µm. Nanoparticle coatings can reduce the cohesive forces between particles. It has been investigated how the fumed silica (SiO2) nanoparticle coating affect the initial flow behavior of standard gas-atomized (15-45 µm) 316L powder and powders with modified particle size distribution (0-45 µm, 15-63 µm, 0-63 µm). It was demonstrated that flowability and bulk density increased as a result of the coating. Relative density and mechanical properties of the LPBF specimen showed similar results compared to the un-coated powder with increased tensile strength. The economic potential of coated powder for AM was demonstrated by the successful LPBF processing of fractions 15-45 µm and 0-63 µm.

DOI:

https://doi.org/10.59499/EP235761175

Authors:

Maximilian Bradler (1), Max Horn (1,2), Georg Schlick (1), Christian Seidel (1,3), Joris Fellinger (4), Gunnar Ehrke (4)

1-Fraunhofer Institute for Casting-, Composite and Processing IGCV Augsburg, Germany

2-Technical University of Munich, Germany

3-University of Applies Sciences Munich, Germany

4-Max Planck Institute for Plasma Physics Greifswald, Germany

Abstract:

Powder bed fusion of metals using laser beam (PBF-LB/M) creates a new platform for the fabrication of complex geometries from high-performance materials. In this regard, the high strength and thermal conductivity of CuCr1Zr lead to great interest in the aerospace and nuclear industries. By understanding the influence of powder properties, the quality of those critical components can be optimized. In this context, the present work investigates the effects of powder properties in PBF-LB/M of CuCr1Zr. For this reason, powders from different suppliers were characterized and processed. Subsequently, the achieved component density, hardness, and electrical conductivity were systematically investigated and discussed to define basic property profiles depending on the powder material.

DOI:

https://doi.org/10.59499/EP235796443

Authors:

Cem Özateş (1), Bülent Genç (2), Onur Ertuğrul (3)

1- R&D Center, Sentes-Bir A.Ş., Turkey

2- R&D Center, Sentes-Bir A.Ş., Turkey

3- Izmir Katip Celebi University, Turkey

Abstract:

Copper has a huge application area thanks to its high conductivity; however, it is difficult to print additively manufactured parts with powder bed fusion methods due to its high reflectivity and thermal conductivity. Binder jetting method has a high potential for use to eliminate these drawbacks. In this study, the effects of particle size distribution and oxygen level of the copper powders on physical, and mechanical properties were investigated. It is seen that 1070°C temperature and 100% H2 atmosphere are highly required. According to Archimedes tests, lower oxygen content (LO) 10-63 powder resulted in higher density compared to LO 15-45 powder. However, image analysis show that 15–45 μm powder yields better densification, and smaller internal porosities. In higher oxygen (HO) 15-45 samples, there is inhomogeneity of pore distribution along the cross section. Consequently, LO 15–45 µm powder yields better tensile properties than HO powder.

DOI:

https://doi.org/10.59499/EP235765498

Authors:

Lea Reineke (1); Regina Schlegel (1); Dr. Sebastian Boris Hein (1)

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

Abstract:

Metal Binder Jetting (MBJ) has an increasing attention in additive manufacturing because of its serial production potential. Finding the most suitable parameterization in MBJ and develop pre-printing tests, can reduce the iteration stages in material-specific process development, which saves costs, effort as well as material resources and printing capacity.

The powder binder interaction of five powders at different packing densities were determined and the wetting behaviors were compared. The equilibrium saturation, the wetting rate and the initial wetting time were analyzed. In order to understand the nature of the resulting porosity at low packing density, various samples were sintered and compared by micrographs.

The results show that an increasing packing density decreases the initial wetting time, increases the equilibrium saturation and lowers the saturation rate. The relationship between wetting behavior and printing parameters, as well as the effect of drying must be investigated further in subsequent studies.

DOI:

https://doi.org/10.59499/EP235740488

Authors:

Marco Zago (1), Alex Rambelli (2), Davide Foschi (2), Ilaria Cristofolini (1)

1- University of Trento - Trento, Italy

2- Powder Metal B.U. – Sacmi Imola s.c. - Imola, Italy

Abstract:

Previous studies have systematically investigated densification in ring-shaped parts. Additionally, the effect of filling parameters on filling and green density was explored, demonstrating the strong influence of the die cavity on the origin of inhomogeneous powder distribution. A uniform density is mandatory for industrial production, so further investigation is necessary, also including the contribution of powder transfer. This work aims at investigating the effect of powder transfer on the density distribution and the geometrical precision in 2-level axi-symmetric parts. Sample geometry was compacted by varying: the filling parameters, powder transfer strategies, and compaction forces. Reference samples were produced by excluding the powder transfer step from the compaction cycle. Green and sintered density distribution were derived, highlighting the effect of filling, powder transfer, and compaction strategies.

DOI:

https://doi.org/10.59499/EP235764659

Authors:

Dr. Christian Mueller (1); Patrick Folkert (1)

1- Emery Oleochemicals, Germany

Abstract:

In this manuscript the influence of two different printing parameters in Fused Filament Fabrication (FFF) Additive Manufacturing process on mechanical properties of metal feedstock-based green parts is investigated. The influence of printing parameters on mechanical properties of sintered parts was analysed in [1], but it is obvious that the additional process steps of debinding and sintering alter the test results and as well might alter the conclusions drawn from such experiment, compared with testing the green parts instead.

Both the nozzle temperature 135 - 145 °C and flow 100 - 105 % in the FFF process were found to have statistically significant influence on tension and elongation at break.

DOI:

https://doi.org/10.59499/EP235730662

Authors:

Shishkina Yulia (1), Baglyuk Genadii (1), Kyryliuk Stepan (1), Kyryliuk Yevheniia (1)

1- I.M.Frantsevich Institute for Problems of Materials Sciences (IPMS NASU), Krzhizhanovsky str., 3, Kyiv, 03142, Ukraine

Abstract:

The article provides the results of the study of the deformation distribution and relative density over the volume of the pore blank during the process of its hot forging in a semi-closed die to produce axisymmetric forgings, as well as the influence of the forging scheme on the phase and structure formation in aluminum composites. The hot forging process was modeled by the finite element method with help of the DEFORM 2D/3D software package. The analysis of the simulation results showed that at the final stage of the process, the strain intensity is almost uniform across the forging volume, with characteristic zones of difficult deformation forming in the upper and lower parts of the cross-section. Experimental studies have shown that, despite the presence of stagnant zones, this hot deformation scheme provides a uniform structure and phase composition of Al-Ti-C composites. The uniformity of the structure and phase composition ensures low anisotropy of properties over the sample volume, and therefore the proposed forging scheme can be used to produce semi-finished products with specified physical and mechanical properties.

DOI:

https://doi.org/10.59499/EP235763938

Authors:

Alexandre Mégret (1), Paco Rodriguez (2), Christoph Broeckmann (3), Véronique Vitry (1), Fabienne Delaunois (1)

1- Metallurgy Unit, Faculty of Engineering, University of Mons, 20 Place du Parc, 7000, Mons, Belgium.

2- Diarotech SA, 19 Rue du Rabiseau, 6220, Fleurus, Belgium.

3- Institute for Materials Applications in Mechanical Engineering, RWTH Aachen University, Augustinerbach 4, 52062 Aachen, Germany.

Abstract:

The trend in the cemented carbide field is to reduce the use of raw cobalt powder in tungsten carbide parts and to develop new binders: indeed, the cobalt price fluctuates extremely due to different factors, mainly its massive use in batteries of electrical vehicles, and its extraction as by-product of copper and nickel mining. The use of a recycled tungsten-cobalt carbide powder skirts the cobalt problem and allows the sintering of WC-Co parts without raw Co powder. In this study, the material is composed of two powders: a powder made from raw materials (WC and Co powders mixed togethers) and a recycled powder (crushed powder containing 7.5 wt.% Co). HIP and SPS are used as sintering technologies before morphological and mechanical characterizations. Mechanical properties of these samples can be tuned with the addition of recycled powder and the parts resulting from the experiments are in total competition with conventional ones.

DOI:

https://doi.org/10.59499/EP235765024

Authors:

R. Carbajales (1); M. Lagos (2); C. Sobrino (1); P. Alvaredo (1)

1- Universidad Carlos III de Madrid. Avda. Universidad 30, 28911, Leganés, Madrid, España.

2- TECNALIA RESEARCH & INNOVATION, 20018 San Sebastián, España.

Abstract:

High-entropy alloys are characterized by their high stability at elevated temperatures, making them a promising alloy family for extreme environments. One field where this characteristic is attractive is in concentrating solar-thermal power (CSP) technology, specifically in plants than employ molten salts (solar salt: 40% KNO3/60% NaNO3) as a thermal storage medium. This study examines the feasibility of using HEAs in components exposed to solar salt, including an original Co-free composition, FeCrMoAlTiNi, and another eutectic composition, AlFeCrCoNi. HEAs were produced using Arc Melting and Powder Metallurgy techniques. The latter processing route was chosen to achieve greater microstructural control, using rapid and ultra-rapid field-assisted sintering methods, such as thermomechanical sintering, Spark Plasma Sintering (SPS), and Electrical Resistance Sintering (ERS). The study results demonstrate improved corrosion resistance over the reference material and offer insights into the microstructural effects of processing routes and their possible relationship with behavior in the presence of molten salts.

DOI: 

https://doi.org/10.59499/EP235764980

Authors:

Srdjan Milenkovic (1,2), Angel Biedma (1,2), Yinuo Guo (3), Paula Alvaredo (2)

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

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

3- Universidad Politecnica de Madrid, Calle del Prof. Aranguren, 3, 28040 Madrid,Spain

Abstract:

The processing method influences the microstructure and therefore, properties of High Entropy Alloys (HEA). In this work, two eutectic high entropy alloys (EHEA) were processed by two different processing methods: arc casting (AC) and powder metallurgical (PM) route comprising powders gas atomization and their consolidation by field-assisted sintering (FAST). The obtained microstructures and properties are compared in order to establish the influence of the processing route on the microstructure of eutectic alloys and the relationship between microstructure, properties, and solidification rate has been established. The processed EHEA were AlCoCrFeNi2.1 and CrFeNi2.2Al0.8. The AlCoCrFeNi2.1 was the first proposed EHEA, which has been thoroughly studied. The CrFeNi2.2Al0.8 EHEA was derived from AlCoCrFeNi2.1 by removing the Co element. Results show that the alloys prepared by the PM possess finer microstructure and higher hardness. The Co-free CrFeNi2.2Al0.8 alloy and AlCoCrFeNi2.1 alloy have similar properties at room temperature when processed by the same method. Introduction

DOI:

https://doi.org/10.59499/EP235785696