Keynote papers receive an extended oral presentation slot in the programme and will go to be published in the journal Powder Metallurgy who sponsors the award.

The EPMA Keynote Papers for World PM2022 are:

Monday 10 October 2022

Using Discrete Simulations Of Compaction And Sintering To Predict Final Part Geometry

Mr Nogueira Gilmar (Université Grenoble Alpes, France)

Abstract: A DEM (Discrete Element Method) model is used to simulate compaction and sintering. A double-action die has been implemented for the compaction stage. The process kinematics are decomposed into loading, unloading, and ejection of the pellet. Interactions between the particles and the die are considered elastoplastic by implementing a large-density model. A qualitative approach is used in the sintering stage. The results are in good agreement with experimental data and FEM simulations from the literature, regarding density gradient, elastic spring-back, and final geometry. The simulations show that the friction coefficient is the primary factor for the density gradient in the pellet. This density gradient induces a non-homogeneous sintering, which results in a final geometry with a so-called diabolo effect. This is the first time that it has been reproduced by DEM with the advantage of more closely reproducing the particulate microstructure of the powder.

Time: 14:30 – 16:00

 Session: Compaction and sintering / Modelling and Sintering

 Room: Auditorium Pasteur

High Strength Ti-Zr Alloys With Balanced Ductility Fabricated By Powder Metallurgy And Additive Manufacturing Routes

Prof Dr Kondoh Katsuyoshi (Osaka University, Japan)

Abstract: The pre-mixed pure titanium (Ti) and zirconium hydride (ZrH2) powder was consolidated by PM process (sintering and hot extrusion) or AM process (selectively laser melting, SLM) to fabricate Ti-Zr alloys, which have excellent corrosion resistance and biocompatibility for human bodies. It was clarified that both materials showed uniform solid-solution of Zr atoms in α-Ti matrix and fine grains due to Zr solute drag, resulting in the significant improvement of tensile strength. In addition, the elongation more than 15% was also obtained in all samples. The quantitative analysis on Zr solution strengthening behavior of both materials was carried out using Labusch model.

Time: 17:00 – 18:30

Session: Light materials/ Titanium Alloys

Room: Rhone 3

Tuesday 11 October 2022

Constitutive Modelling Of Solid State Sintering Of Cemented Carbides

Dipl-Ing Rosenblad Louise (KTH, Sweden)

Abstract: From a previously developed constitutive model of cemented carbide, the powder size- and configuration can be used to simulate the densification during the sintering process. However, small differences in experimental execution cannot be accounted for in the simulation, making the model sensitive. Here, we study how well the developed constitutive model can capture the experimental results of a dilatometer test. Three different experiments were performed where the only difference was the transition between the debinding and sintering process. From parameter adjustments, it is seen that the constitutive model is more suited to a certain experimental setup, which is a limitation of the model.

Time: 14:30 – 16:00

Session: Hard Metals/ Modelling and testing

Room:  Bellecour

Development Of X40CrMoV5-1 (H13) On Binder Jetting Technologies

Dr Ing Reynaud Christophe (CETIM, France)

Abstract: Cetim has launched further material project development on binder technologies. This work deals with the development of the tool steel X40CrMoV5-1 or H13 on two Metal Binder Jetting technologies, namely DM P2500 (Digital Metal) and Lab P-1 (Desktop Metal). The whole MBJ H13 has been developed by adjusting the 17-4PH powder printing parameters and by developing a specific sintering recipe by using a vacuum metallic furnace under controlled atmosphere (one step debinding sintering). The presentation will be focused on sintering development. Controlling the final carbon content and achieving high density level without excessive component distortion by using SLPS process are the main challenges to overcome. The microstructure and the mechanical properties are compared. For both technologies, as sintered mechanical properties are consistent with data coming from MIM H13 materials and wrought materials.

Time: 17:00 – 18:30

Session: Ferrous materials/ Steels for Binder Jetting

Room: Auditorium Pasteur

Wednesday 12 October 2022

Solid-state Processing Of Surplus Aluminium Alloy Powders Through A Combination Of Field Assisted Sintering Technology And Hot Rolling

Dr Graham Simon (The University of Sheffield, United Kingdom)

Abstract: Metal additive manufacturing techniques typically operate using powders with limited particle size ranges, but atomisation processes produce significant amounts of particles outside these ranges, resulting in an accumulation of out-of-size specification metal powders without a clear use case. Field assisted sintering technology (FAST) can provide an alternative, solid-state processing route to consolidate these powders into billets for subsequent processing, or directly into near-net shape components. In this study, surplus powders of A20X, an aerospace approved aluminium alloy developed by Aluminium Materials Technologies (ECKART GmbH), were processed using FAST and subsequently hot rolled to produce sheet material. Tensile properties were similar to hot rolled conventional cast material and comparable to additively manufactured product. This indicates that FAST is an effective option for processing surplus metal powders, whilst improving sustainability in the additive supply chain.

Time: 08:30 – 10:00

Session: FAST/ Recycling and Shape Control

Room:  Rhone 3

Brake Discs Made Of Aluminum Matrix Composites

Dr Ing Trapp Johannes (Fraunhofer IFAM, Germany)

Abstract: Aluminum-based metal-matrix-composites (AMCs) show attractive properties to meet the growing demand for lightweight construction for example in the automotive and aerospace industries. Limiting factors are difficulties in processing and machining as well as comparably low operating temperatures. The first issue is addressed using spark plasma sintering (SPS) to produce fully dense net-shape compacts. Therefore, the electrical properties of the powders must be understood and adjusted. To increase operation temperature, alloys with thermally more stable Al3Fe dispersoids, certain intermetallic phases, or complex constitutional alloys have been investigated. The latter are developed with the help of a systematic selection process to calculate the thermodynamic and kinetic criteria to predict the phases formed. Those AMCs show melting temperatures above 1000 °C while keeping the density below 4,5 g/cm³. Aiming for compressive strength > 800 MPa and elongation to fraction >1 % makes the materials suitable e.g. for front wheel brake disc applications.

Time: 11:00 – 12:30

Session: Light materials/ Al Alloys

Room: Auditorium Pasteur

Rheological Characterization Of Water Atomized Tool Steel Powders Developed For Laser Powder Bed Fusion By Supervised And Unsupervised Machine Learning

Mr Mutel Denis (Université Laval, Canada)

Abstract: Metal powders developed for powder-bed additive manufacturing processes need to achieve specific flow characteristics to be considered suitable. However, the relationship between powder flow and the morphological characteristics of individual particles can be difficult to establish. In this context, artificial intelligence appears to be the perfect tool to clarify the imprecision surrounding this type of interaction. The work summarized in this manuscript first uses a neural network architecture (Mask R-CNN) allowing the segmentation of individual water-atomized particles in micrographs acquired in scanning electron microscopy. The micrographs of individual particles or their shape descriptors (roundness, elongation, etc.) are then processed using different machine learning (ML) strategies, supervised or not, to relate the information collected on individual particles with the rheological properties of powder specimens. The approach developed aims to acquire new knowledge regarding specific particle characteristics that are required to optimize powder flowability for laser powder bed fusion.

Time: 17:00 – 18:30

Session: Digitization/ Digitalization 1

Room:  Bellecour

Thursday 13 October 2022

Influence Of Oxygen In The Production Chain Of Metallic Glasses Via Laser Powder Bed Fusion

Ms Soares Barreto Erika (Leibniz-Institute for Materials Engineering IWT, Germany)

Abstract: Laser powder bed fusion of metals (PBF-LB/M) is advantageous for manufacturing bulk metallic glasses with size and geometrical freedom. However, the oxygen uptake along the production chain can negatively impact the generation of high-quality, amorphous parts. In this context, Cu-Ti-based alloys were gas-atomized and additively manufactured using commercial and high purity feedstocks. The oxygen absorption in each processing step was tracked and related to the amorphous phase formation and glass-forming ability (GFA) of alloys. Results show an increasing oxygen absorption, considerably influenced by the starting feedstock, especially for commercial purity. In high purity material, the most contribution is inherent from the powder oxygen content. Findings reveal the lack of influence of the oxygen content in the GFA. TEM analysis of commercial powder and PBF-LB/M sample show uniform and featureless micrographs, displaying the absence of oxygen-induced nucleation. The present contribution enhances the qualification and economic processability of amorphous metals by PBF-LB/M.

Time: 08:30 – 10:00

Session: AM beam based/ Special Materials

Room:  Bellecour

Fabrication Of Tailored Ti-based Materials By Conventional Powder Metallurgy For Bone Implant Applications

Dr Luis Olmos (Universidad Michoacana de San Nicolás de Hidalgo, Mexico)

Abstract: This works proposes a methodology for fabricating materials with specific characteristics tuned for replacing human bones. A Ti64 alloy powder is used as the base materials and it is mixed with Ag, Ta, TiN and salt particles to obtain different features. A knee-bone like component is fabricated, including a highly porous core of Ti64/25Ta/5Ag and compact outer of Ti64/5Ag that is supposed to improve corrosion and osseointegration. Besides, a harder top surface in Ti64/10TiN composite should increase the wear resistance. The green component is sintered at 1260°C in argon. Its stiffness is close to the one of bones thanks to the added porosity, which also provides a permeability close to the one reported for trabecular bones. Tribocorrosion behavior in simulated body fluid is improved by TiN addition. In conclusion, the proposed processing route is able to produce complex components fulfilling specific features required for human bone replacement.

Time: 11:00 – 12:30

Session: Applications/ Biomedical

Room: Roseraie