Euro PM2024 Proceedings

Authors:

Hossein Besharatloo (1,2,3), Ahmed-Ameur Zegai (4), Saghar Fooladimahani (1), Caterina Chirico (3), Luis Llanes (1), Begoña Ferrari (3), Antonio Javier Sanchez-Herencia (3)

1- CIEFMA/CMEM/EEBE - Universitat Politècnica de Catalunya, Barcelona, Spain

2- COLFEED4PRINT, Madrid, Spain

3- ICV-CSIC, Madrid, Spain

4- Laboratory of Materials Sciences and Engineering (LSGM), Faculty of Mechanical Engineering and Process Engineering, University of Sciences and Technology Houari Boumediene, Algiers, Algeria

Abstract:

The powder composition and sintering process significantly influence the microstructure, phase composition, and mechanical properties of WC-based composites. The precise control of both chemical composition and sintering conditions is crucial for tailoring these materials to meet specific requirements across diverse applications, such as cutting tools, wear-resistant components, and various industrial uses. The study comprehensively assesses: I) the impact of varying nickel content, and II) the influence of sintering methods, including conventional and Spark Plasma Sintering (SPS), on the final microstructures and mechanical properties of the WC/Ni composites. In doing so, two sets of WC/Ni composites (containing 5 and 10 vol% Ni) were sintered using SPS and conventional methods. The microstructural analysis included FESEM and XRD, while mechanical properties were evaluated at different length scales including Vickers hardness, and fracture toughness. This detailed examination contributes valuable insights for enhancing the microstructural design of WC/Ni composites.

DOI:

https://doi.org/10.59499/EP246281827

Authors:

Paul Baret (1,2), Xavier Boulnat (2), Yann de Carlan (1), Laurent Chaffron (1), Damien Fabrègue (2), Joël Malaplate (1)

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

2- Université Lyon, CNRS, INSA-Lyon, MATEIS UMR5510, France

Abstract:

Austenitic steel was the reference cladding material in sodium cooled fast neutron nuclear reactors. These alloys exhibit good high temperature mechanical properties and they can withstand very high irradiation doses. To further increase the performance of these alloys, two distinct ways of improvement are possible: oxides dispersion strengthening or ultra fine grain microstructure. In order to achieve the desired enhanced material, powder metallurgy and in particular mechanical alloying route is promising. However, the high ductility of austenitic steel significantly reduces the powder production yield and worsens the supersaturation of oxides during mechanical alloying. To overcome this issue, multiple batches were produced using high-energy horizontal attritor at times ranging from 5 to 40 hours and consolidated by Spark Plasma Sintering (SPS). This paper tackles the characterization of powders after mechanical alloying and SPS compacts.

DOI:

https://doi.org/10.59499/EP246274627

Authors:

A. Kirchner (1), U. Gaitzsch (1), D. Dorow-Gerspach (2), B. Distl (3), M. Franke-Jurisch (1), C. Zhong (1), T. Weißgärber (1,4)

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

2- Forschungszentrum Jülich, Institut für Energie- und Klimaforschung - Plasmaphysik, Germany

3- Plansee SE, Austria

4- Institute of Materials Science, Technische Universität Dresden, Germany

Abstract:

For refractory metals additive manufacturing of near net shape parts represents an attractive opportunity, in particular for complex geometries. The combination of high melting point, thermal conductivity and brittleness represents a challenge for fusion processes. Electron beam powder bed fusion (PBF-EB) facilitates preheat temperatures above 1000°C and vacuum processing with negligible oxygen contamination. Elemental tungsten and molybdenum were PBF-EB processed to high density from spherical and non-spherical powders. The resulting microstructure is characterized by large grains elongated in build direction and texture. Accordingly, the potential for the mechanical strength of defect-free PBF-EB refractory metals corresponds to conventionally fabricated material in recrystallized condition. The cracking behavior of tungsten tiles under extreme thermal shock was analyzed. Generated test geometries include thin-walled components and lattice structures. The Mo9Si8B alloy required 1100°C preheat temperature for crack-free processing. The microstructure is fine-grained with coarsening in the lower part. The bending strength exceeds 1200 MPa at 1000°C.

DOI:

https://doi.org/10.59499/EP246281479

Authors:

Patrick Korir (1,2,3), Maheswaran Vattur Sundaram (1), Kumar Babu Surreddi (2), Farnoosh Forouzan (1,2), Dimitris Chasoglou (1), Marta-Lena Antti (2,3)

1- Höganäs AB, Sweden

2- Division of Materials Science, Luleå University of Technology, Sweden

3- Wallenberg Initiative Materials Science for Sustainability, Division of Materials Science, Luleå University of Technology, Sweden

Abstract:

In PM steels, alloying through master alloy (MA) addition enables the introduction of oxygen-sensitive elements such as Cr, Mn, and Si. These elements offer cost-effective and sustainable alternatives to Cu and Ni, enhancing hardenability and performance. This study investigates the atomisation of Fe-Cr-Mn-Si-C MA powders using three different techniques: water atomisation, gas atomisation, and gas atomisation-water cooling. The MA powders were sieved into two size fractions and mixed with Fe – 0.85 wt.% Mo pre-alloyed base powder and graphite. MA powder characterisation, compressibility, and dilatometry-sintering experiments were performed to evaluate the different atomisation techniques, and liquid phase formation at various sintering temperatures. Additionally, industrial sintering trials were conducted, and mechanical properties were assessed to understand the behaviour of sintered samples. The results indicate that MA addition improves the hardenability and performance, especially after sintering above 1200°C, once the MA melting and alloy homogenisation have occurred.

DOI:

https://doi.org/10.59499/EP246281345

Authors:

Sunil Raghavendra (1), Sasan Amirabdollahian (2), Matteo Perini (2), Marco Chemello (3), Matteo Benedetti (1)

1- Department of Industrial Engineering, University of Trento, Trento, Italy

2- ProM Facility, Trentino Sviluppo S.p.A, Rovereto, Italy

3- Sicor S.p.A, Rovereto, Italy

Abstract:

With the current development in additive manufacturing (AM) processes, such as Laser directed energy deposition (L-DED), efficient usage of raw materials is possible. With the aid of this L-DED process, we aim to develop an efficient way to reduce the use of bronze in worm gears. Our objective is to fabricate worm gears by applying CuSn10 (bronze) alloy onto a stainless steel tooth created through the L-PBF process. We assess the impact of laser power, feed rate, scanning speed, and scanning strategy on the deposition process. The deposited cross-sections undergo analysis for porosity, hardness, dilution, and microstructure at various locations along the tooth profile.

DOI:

https://doi.org/10.59499/EP246283629

Authors:

Mohammadreza Jandaghi (1,2), Johan Moverare (1,2)

1-Division of Engineering Materials, Department of Management and Engineering (IEI), Linköping University, Sweden

2-Wallenberg Initiative Materials Science for Sustainability, Department of Management and Engineering (IEI), Linköping University, Sweden

Abstract:

The sustainability of Laser Powder Bed Fusion (L-PBF) in metallic component production hinges on effective powder reusing, given the significant unsolidified feedstock residue. This study evaluates the influence of powder reuse on phase evolutions using thermodynamic simulations via Thermo-Calc software. Both virgin and five-time reused powders of austenitic steel 316L (SS316L) were examined alongside printed parts. Results indicate unavoidable Rhodonite (MnSiO3) inclusions due to its high oxidation affinity. Rapid solidification produces ferritic single crystal particles from hot spatters. Sieving inefficiencies allow smaller oxide particles to persist, increasing oxide fractions in printed parts. Scheil diagrams show that while minor oxygen does not impact solidification, increased dissolved oxygen promotes Spinel (MnCr2O4) formation and inclusion clustering, serving as potential nucleation sites for ferrite. Tensile sample analysis reveals that, despite the pinning effect of fine oxide particles, increased inclusion size in reused samples compromises tensile strength.

DOI:

https://doi.org/10.59499/EP246281053

Authors:

Neyder A. Sandoval (1), Edwin A. Murillo (2), Sophia A. Tsipas (1)

1- Materials Science and Engineering Department, IAAB, Universidad Carlos III de Madrid, Spain

2- Chemistry Department, Universidad Francisco de Paula Santander, Cúcuta, Norte de Santander, Colombia

Abstract:

Sinter-based additive manufacturing of metallic materials offers advantages in terms of design and efficiency but poses environmental concerns due to the use of chemicals and the generation of pollutant gases during the elimination of binders which are harmful to the environment. To improve this problem, the study of biopolymeric binders derived from renewable sources is proposed. This work explores composite extrusion modelling of metallic or metal-ceramic alloys using biopolymers to produce environmentally friendly feedstocks. Comprehensive evaluation of biopolymer blends based on poly lactic acid and polyvinyl alcohol were carried out for their use as binders. A study of critical solidity loads, microstructural, rheological characterisation, densification, and homogenisation, studies were performed.

DOI:

https://doi.org/10.59499/EP246282804

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:

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

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

Authors:

Arnaud Fregeac (1), Méyane Hurtault (1), Céline Larignon (1), Yannick Beynet (1), Romain Epherre (1)

1-Norimat, France

Abstract:

Sinter Based Additive Manufacturing (SBAM) processes are receiving much attention as an alternative to LPBF processes for the rapid production of metal and ceramic components with reduced cost and environmental impact. On the other hand, the sintering step is sometimes difficult to perform for green parts from SBAM process resulting in high residual porosity. This paper proposes a versatile alternative with FAST/SPS hybridisation. The FAST/SPS process is recognised as an R&D method capable of producing high performance parts from a wide range of materials. In recent years, significant progress has been made in overcoming the two main limitations of the technology: production capacity and geometric constraints. An important industrial breakthrough is presented here, with the development of a unique hybrid process that enables the consolidation of 3D SBAM parts by FAST/SPS. It allows green parts to be fully densified (porosity <1%) immediately after printing in a single step and with less than 2 hours of thermal treatment.

DOI:

https://doi.org/10.59499/EP246276973