Middle of May the European Powder Metallurgy Association (EPMA) organised the Seminar ‘Powder Based Metal Additive Manufacturing Technologies‘
The seminar was hosted by the Centre for Additive Manufacturing – Metal (CAM2) at Chalmers University of Technology in Gothenburg. Covered were the entire metal Additive Manufacturing (AM) process chain, from metal powders, Design for AM, the different metal AM processes, quality assurance, standardization in AM to post-treatment processes. Included were also visits to ARCAM, Hoganas – Digital Metal and a tour of the Chalmers CAM2 facilities.
Day 1
Depending on registration, the program started with the visit to ARCAM AB [General Electric]
Background ARCAM is a manufacturer of Electron Beam Powder Bed Fusion systems (E-PBF). ARCAM is calling the technology Electron Beam Melting (EBM). [General Electric (GE) acquired ARCAM in 2017]
Daniel Wexell from ARCAM welcomed the group and provided a detailed introduction to EBM technology. The presentation started with technical fundamentals as the progress made since EBM technology was introduced in 2003. Then, we dived deeper into details of operational constraints like power vs. usable build space as the lifetime of filaments and cathodes. We also talked about applications as the in-house use of E-PBF within GE, like the Titanium-Aluminide compressor blade production at AvioAero. After the presentation, we got the chance to have a closer look at and inside a Q10plus and Q20plus system.
Daniel Wexell getting into details of the ARCAM Q10plus system
Back at Chalmers University, the seminar started. Kenan Boz, Technical Manager of, EPMA, welcomed the audience and provided an introduction to EPMA. Kenan’s presentation focussed on general tasks of EPMA as the current activities. Projects like the European Sector Skill Strategy Additive Manufacturing (SAM / Skills4AM) were just one example of the valuable work of EPMA. Eduard Hryha Professor at Chalmers and Director of the Centre of Additive Manufacturing Metal (CAM2 ) shared an introductory overview of powder-based metal AM technologies. The presentation from Mattias Fager from Arcam which doubled up a bit with the visit at ARCAM in the morning. Juha Kotila from Electro Optical Systems (EOS) presented on EOS M line systems. He explained productivity gains through multi-beam systems and different pointed out different configurations for production applications. Dipl-Ing Claus Aumund-Kopp from Fraunhofer IFAM shared insights on Metal Binder Jetting Technologies (MBJ). Comparing, productivity and material properties of L-PBF systems with the status quo of Metal Binder Jetting. He explained the relevant process parameters affecting material properties. He was pointing out that simulation and compensation of shrinkage still can be considered ‘the holy grail’…challenging claims of major Binder Jetting OEMs. He also invited the audience to the IFAM Workshop Sinter-Based Additive Manufacturing 18.09.- 19.09.2019 in Bremen. Assoc. Prof. Joel Andersson from University West Sweden presented on Direct Energy Deposition (DED) with powder vs. DED with wire. Explaining the higher productivity of wire DED wand highlighting applications of DED in Aerospace. Hannes Freisse from BeAM continued with a presentation on Process Development for additive manufacturing by DED. Katarina Widström, from the Swedish Institute for Standards (SiS), provided an overview of current activities of SiS for Standardisation in Metal AM. Katarina explained that currently 16 partners (Institutes as companies) are supporting the work of SiS, which is closely aligned with DIN/ISO as ASTM to avoid conflicting standards. Ola Lyckfeldt from RISE IVF presented on the Characterisation of powder for AM. Addressing, coarsening effects and causes changes in flowability of metal AM powders. But also oxygen pick up by the smaller corn size fraction. Especially, interesting was to learn about RISE IVF’s Powder Layering Tester. A test rig which allows creating powder beds with different wipers at variating recoating speeds. These factors are leading to significant variations in the packing density of the powder bed. Then Eduard Hyra explained the structure, capabilities and tasks of the Centre of Additive Manufacturing Metal (CAM2 ). After his presentation, the audience split up in smaller groups to tour the facility. The L-PBF setup includes an EOS M290 as an EOS M100 system. A personal highlight to see was the extraction ducts which can be moved over the doors when working with the process chamber opened. Further, we toured several labs and had the chance to see some of the (unique) testing instruments of Chalmers /CAM2 .
IMAGO LEAP – Atom Probe Tomography (APT)
Later Day One was concluded with networking over a nice dinner function.
CAM2 L-PBF setup. (Note the moveable ducts for extraction of airborne powder particles)
Day 2
The second day started with a presentation by Prof. Eduard Hryha.
Professor Hryha presented on Powder Recycling in AM He focussed on powder degradation and aging effects of recycled AM powders. The work presented focussed on Hastelloy X, 1.4404/316L and IN718 powders which had been run in E-PBF and L-PBF for up to 14 cycles. Further discussed were oxygen pick-up on powders as benefits of using Helium over Argon as a process gas in L-PBF.
Prof. Lars Nyborg, also from Chalmers and Co-Director CAM2 presented on the Synthesis of Novel Alloys by AM, explaining why 316L/1.4404 is a material easy to process with L-PBF by highlighting the difficulties of more challenging materials.
Dr. Pilvi Ylander from EOS shared his presentation an overview of techniques for Quality Assurance in LPBF. Pilvi explained the different strategies of process monitoring techniques used by the major OEMs for L-PBF systems. From on-axis photodiodes to pyrometer solutions as visual and thermal camera systems. Pilvi explained in detail EOS strategy for process monitoring.
Leandro Feitosa from Sandvik discussed in Plan It – Print It, PERFECT IT Sandvik’s usage of metal AM technologies. Leandro explained how Sandvik is working in-house, as with customers, on applications like drilling heads and machine tool holders. Leandro highlighted the productive increase through the integration of cooling fluid channels and usage of topology optimization to improve parts made through L-PBF and Metal Binder Jetting.
Jim Shipley from Quintus Technologies presented on The use of Hot Isostatic Pressing (HIP) in the production of additively manufactured stainless steel parts. James explained the advantages of HIP treatment of metal AM parts, closing internal porosity and homogenising microstructure.
Dr. Agustin Diaz, REM Surface Engineering Augustin’s presentation was named ‘Surface texture optimization of AM metal components for improved mechanical performance: Understanding the surfaces of AM metal components‘. Augustin explained what kind of surface finishes are achievable with REM’s proprietary surface finishing process. Examples of the improved surface of metal FDM. L-PBF as E-PBF parts were shown, most of them had an impressive mirror finish. It was interesting when Augustin called the outer boundary scan of L-PBF parts ‘make-up’. He explained that very often defects lay in between outer boundary and hatch. That’s why make-up. So Augustin was questioning if the outer boundary is always needed if parts undergo surface post-treatment.
Olivier Tabaste from MSC Software Corporation presented on Value of Simulation in Machine Learning of Smart AM Oliver explained how Artificial Intelligence Deep learning can be used to speed up simulations without simplifications of the model.
Pierre Forêt from Linde Pierre presented about Linde’s holistic approach to powder-based metal AM technologies. Linde takes every step of the process chain into account, from the atomisation, packaging, storage, sieving, the actual AM process, recycling, drying to mixing as post-processing of AM components. Pierre also explained the capabilities of Linde’s AM Lab in Munich. Here the company is looking at the effects of Oxygen on Titanium or Hydrogen occurring when processing Al-alloys with L-PBF. Further, Pierre shared some results of the shared work of Linde in collaboration with CAM2 on the usage of Helium as a process gas. Finally, Pierre addressed the importance of sequential usage of Personal Protective Equipment (PPE) when working with metal powders and safety concerns regarding working with inert gas.
Patrik Ohdin from Freemelt shared in his presentation Open Source AM for Materials R&D the aim of Freemelt’s open E-PBF platform. Patrik explained the companies aim to dramatically increase the number of materials/process parameters available for E-PBF. The Freemelt ONE system, Freemelt’s first machine, is designed especially for research and material process parameter development. Therefore the ONE has a small build envelope, allowing to work with limited amounts of material. Where the 6kW electron-gun certainly won’t present a limiting factor. https://freemelt.com/ Ralf Carlström from Digital Metal Ralf’s presentation Serial production of 3D printed high precision components provided a good overview as detail insights into the Metal Binder Jet technology by Digital Metal. With the first system installed in 2015 the company focussed on part production as a service. The first production application in 2017 led to on-premise installations with selected customers. Finally, the DM P2500 system is generally available on the market. Further, Ralf explained how the material range has expanded from Ti64 and 316L/1.4404 stainless to high-nickel alloys Inconel265 and MA247. u He also explained the reason for the unusual layer thickness of 42 microns which simply has to do with the XY-print resolution. It’s just to have cube-shaped voxels with a uniform lengthed edge.
Day 3
On the third day, the tour to Digital Metal and Höganäs AB was on the itinerary. The two-hour was another good opportunity for more networking.
Arrived at Digital Metal we learned in a short presentation more about the material properties of Digital Metal’s Binder Jetting process. Further, we got an introduction to the specific design-rules for Metal Binder Jetting for an optimal design suiting the two-step process. The print of the green part is only half the job. As the final shape and accuracy are determined by the sintering. Custom ceramic supports can mitigate sagging of overhanging areas during sintering. After this, Ralf Carlström guided the group through the machine assembly area as the job-shop production facilities. Ralf explained in detail the advantages as the challenges of Digital Metals metal binder jetting technology. He showed us the, so far the largest part built on one of Digital Metal’s machines. But the usual production applications are smaller highly complex parts, where no support structures can be applied. Ralf also showed us the automated powder removal system DPS1000 for enhanced automation and maximum powder-efficiency.
After a nice lunch in the old pottery production facilities of Höganäs AB the group went to receive safety gear. Equipped with safety boots, high vis-vests and earplugs entered the production plant. We toured the entire plant and learned how Höganäs turns iron ore into metal powder. Höganäs powders can be found in parts of almost any automotive around the world. In the late afternoon, we returned to Gothenburg what concluded the seminar.
Seminar attendee group photo Credit: EPMA
Summary The EPMA Additive Manufacturing Seminar was great to learn more about the different metal Additive Manufacturing technologies. Industry experts as researchers provided information on all levels, from fundamentals to cutting edge research. The seminar also provided many opportunities to network and discuss the topics in detail one to one. For more information on the activities and events check the EPMA website www.EPMA.com