Additive Manufacturing: Beyond on the Beam IV: Process Development and Optimization
Sponsored by: TMS Materials Processing and Manufacturing Division, TMS: Powder Materials Committee, TMS: Additive Manufacturing Committee
Program Organizers: James Paramore, Texas A&M University; Daniel Lewis, Texas A&M University; Kyle Tsaknopoulos, Worcester Polytechnic Institute; Paul Prichard, Kennametal Inc.
Tuesday 8:00 AM
March 21, 2023
Room: 24A
Location: SDCC
Session Chair: Kyle Tsaknopoulos, Worcester Polytechnic Institute; Paul Prichard, Kennametal Inc.; Daniel Lewis, Texas A&M University
8:00 AM Invited
Engineering Powder Characteristics of WC-Co for Binderjet Processing: Paul Prichard1; Zhuqing Wang1; Hadi Miyanaji1; 1Kennametal Inc.
Binderjet additive manufacturing process has grown from an innovative rapid prototyping method to a commercial manufacturing process in the past 30 years. The process relies on the inkjet printing technologies, which allow for deposition of organic binding agents in layers of a loose powder bed to create a green shape that can be subsequently sintered into a dense article. Metallic powder feedstock is typically gas atomized and the characteristics are optimized for flowability and sinterability. Recent work in the past few years has demonstrated that a sub-optimal powder flowability improves the resistance to particle ejection due to droplet impact. This presentation will discuss engineered powder characteristics and the interdependence between dispensing, spreading, powder ejection, green strength and sintering on microstructure, mechanical properties, and dimensional control.
8:20 AM
Electroplating Powder for Cold Spray Applications: Elizabeth Hodges1; Gilbeom Seo1; Victor Champagne2; Robert Hyers1; 1University of Massachusetts-Amherst; 2Cold Spray Innovations International
Cold spray is a processing technique in which powder particles are accelerated toward a substrate on which they deposit and build a wrought coating. In this process it is essential to balance the velocity of the particle, the properties of the particle, and of the substrate; otherwise, the particles may either fail to deposit or may erode the substrate. Current work is exploring approaches that would allow for harder particles to be deposited on the surface of more ductile substrate without eroding the substrate. One approach to accomplish this is electroplating a softer coating on the hard powder. However, electrodeposits readily form a continuous layer binding the particles into a matrix, rather than uniformly coating the powders. A novel approach to electroplating has been successful with several different combinations of coatings and powders.
8:40 AM
A New Approach to the Manufacturing of Metallic Lattice Parts by Combining Polymer Additive Manufacturing and Electroplating: Roozbeh Neshani1; Olgun Yılmaz1; Atalay Balta1; Davis McGregor2; Sameh Tawfick2; William King2; İshak Karakaya1; Sezer Ozerinc1; 1Middle East Technical University; 2University of Illinois at Urbana-Champaign
We report on the development of a new polymer-metal composite structure that combines additive manufacturing and electroplating. The process starts with Digital Light Synthesis, a rapid vat photopolymerization process, that provided rigid polyurethane honeycomb structures. The honeycomb parts had a 9 × 8 cell arrangement with overall dimensions of 48.5 mm × 48 mm × 30 mm. 100 µm-thick NiCo electroplating on these structures provided a 6-fold improvement in elastic modulus and a 3-fold rise in strength, compared to the uncoated parts. The developed polymer-metal honeycomb composite architecture provides a new approach to the design and implementation of lightweight structural materials and impact-absorbing parts. The highly scalable polymer AM and well-established electroplating techniques offer a fast and cost-effective alternative to the direct metal printing of cellular structures and lattice parts.
9:00 AM
Optimization of Mechanical Performance of Cold Sprayed Niobium: Brady Butler1; Van Pham2; Bradley Robinson2; Charles Ribardo2; Ion Powell2; Zachary Nolan2; Isaac Nault1; James Paramore1; 1DEVCOM-ARL; 2Texas A&M University
Refractory metals find significant use in aerospace, defense, and nuclear applications where environments are extreme and dynamic. The development of cold spray additive manufacturing processes enables the efficient use of refractory metals as a coating material in these advanced applications where operating temperature, strength, ductility, and wear are critical performance metrics. This research discusses the rapid optimization of heat treatment processes for improving the performance of cold sprayed niobium with a focus on improving the overall toughness of the coating. Heat treatments were performed in a vacuum atmosphere, and tension tests were conducted using a miniaturized sample proportional to the ASTM E8 standard. Hardness, microstructure, and tensile behavior provide a preliminary assessment of performance in extreme environments.
9:20 AM
Through-Process Experimental Approach for Optimization of Powder Feedstock for Cold Spray Additive Manufacturing: Kyle Tsaknopoulos1; Bryer Sousa1; Jack Grubbs1; Danielle Cote1; 1Worcester Polytechnic Institute
This work employs a Through Process Experiment (TPE) systematic approach to study the relationship between powder properties, cold spray (CS) processing parameters, and consolidated specimen behavior through a combination of characterization and computational models. This and TPE approach allows for the systematic isolation of variables that can affect powder and CS properties. In this study, various heat treatments were applied to Al 6061 powder and used as CS feedstock using industry-standard processing parameters to study the effect of thermal pre-treatment of Al 6061 powder on cold spray properties. Techniques including SEM, EDS, XRD, nanoindentation and particle compression, tensile and indentation plastometry testing, corrosion testing, and fatigue testing were used to characterize the properties of both the feedstock powder and CS deposits. Computational thermodynamic modeling was used to guide microstructural interpretation. An additive yield strength model was employed to quantify the strengthening components introduced through the CS process.
9:40 AM Break
9:55 AM
Liquid Metal Jetting Based Additive Manufacturing of Cu-Al-Fe Bronze Alloy: Kellen Traxel1; Chinthaka Silva1; Eric Elton1; Viktor Sukhotskiy1; Luke Thornley1; Andrew Pascall1; Jason Jeffries1; 1Lawrence Livermore National Laboratory
Metal-AM processes involve inherent thermal transients and phase transformations during processing that can lead to cracking, print failure, and variation in mechanical properties. These areas are largely unexplored for liquid metal jetting (LMJ) based-AM, which requires only raw ingot and involves different thermal processing characteristics in comparison to other metal-AM methods. Bronze alloys based on Cu-Al-Fe parent alloy system exhibit several solid-state phase transformations from the molten state down to room temperature, which makes them an interesting candidate for study via LMJ. We present results of printing studies where bronze alloy C954 (Cu-Al-Fe) is jetted onto metallic substrates at various processing parameters. High-magnification imaging, analysis, and characterization of the printed material demonstrates the vast differences in microstructure and processing characteristics at various input processing parameters, leading to a better understanding of the properties of these materials when processed via LMJ. Prepared by LLNL under Contract DE-AC52-07NA27344. LLNL-ABS-837361.
10:15 AM
Recycled Ti-6Al-4V Powder Processed by Fusion Deposition Modelling (FDM): Marcus Rackel1; Stephan Schulze1; Kai Steinberg1; Henrik Lüneburg1; Florian Pyczak1; Wolfgang Limberg1; Thomas Ebel1; 1Helmholtz-Zentrum Hereon
An economic drawback of powder based additive manufacturing methods is the high cost of powder compared to cast materials. However, if the material loss in the production of machined complex geometries is taken into account, the cost-loss can be compensated. The use of recycled materials that do not originate from the primary powder production cycle offers further potential for cost reduction. In the present contribution, the use of Ti-6Al-4V powder generated via a recycling route is combined with FDM processing. The starting chip material for powder production comes from aviation production leftovers. The chips were cleaned and formed into cylindrical electrodes. Spherical powder was then produced using the Electron Induction Guided Atomization process. The tensile strength of the FDM parts was validated against parts processed by MIM, both made out of the same recycled Ti-6Al-4V powder feedstock.
10:35 AM
Solid State Additive Manufacturing of Oxide Dispersion Strengthened FeCrAl Alloy through Metal Extrusion Method: Saumyadeep Jana1; Zachary Kennedy1; Amrita Lall1; Michelle Fenn1; 1Pacific Northwest National Laboratory
Metal additive manufacturing methods not relying upon melt solidification for densification are gaining interest, since they provide better control on microstructure, composition, and residual stress in fabricated components. Metal extrusion additive manufacturing (MEAM) is a solid-state additive manufacturing method that works on the principle of shaping, debinding, and sintering steps. Development of MEAM method for oxide dispersion strengthened (ODS) FeCrAl alloy has been carried out. FeCrAl alloys are a special class engineering alloys with bcc crystal structure and provide good high temperature strength and oxidation resistance. Incorporation of nano-sized reactive element oxide particles further improves oxidation resistance and creep strength. Our work demonstrated successful fabrication of polymer-bound FeCrAl filaments with 65% metal content by volume. Subsequently, composite FeCrAl filaments were used to print various test coupons that were used to develop effective binder removal methods and the high-temperature sintering method, to achieve <1% porosity by vol. in the built part.
10:55 AM
Solid State Additive Manufacturing of Magnesium via Friction Stir Deposition: Sameehan Joshi1; Shreyash Patil1; Shashank Sharma1; Sangram Mazumder1; Daniel Riley1; Shelden Dowden1; Rajarshi Banerjee1; Narendra Dahotre1; 1University of North Texas
Additive friction stir deposition of AZ31BMg alloy was explored using MELD technique. The process involved a hollow steel tool consisting of a coaxial 1cm2 square cavity through which bar stock of AZ31BMg was pushed against the base plate. The tool was rotated at 400rpm and translated with the velocities from 4.2 to 6.3mm/s to deposit 5 layers of dimensions 140x40x1mm3. Thermocouples embedded within the base plate monitored temperature evolution as the deposition was carried out. Vital process attributes such as tool torque and actuator force were monitored using onboard sensors and converted to overall heat input. Deposition temperatures and strain rates were estimated using process attributes. The deposited material evolved a marginally refined microstructure compared to the feed stock consisting of α-Mg phase with predominantly basal texture. The refinement in microstructure was reflected in a minor improvement in the Vickers hardness of the deposits compared to the feedstock
11:15 AM
Teaching Printers How to Print: From G-Code to Integrating AI and Cloud Computing into Additive Manufacture: James Hardin1; Erick Braham1; Jennifer Ruddock1; Nicholas Arn1; 1Air Force Research Laboratory
Ideally, automation and artificial intelligence code developed by research labs will flow seamlessly into applications around the country. In practice, poor documentation, implementation challenges, and intellectual property issues significantly slow or stop technology transition. We are using direct-ink write (DIW) AM as a prototypical high-mix low-volume manufacturing process for exploring various tools to accelerate digital technology adoption. This presentation will show our progress from traditional G-Code automation for automation to a cloud-edge architecture with containerized modular microservices. We will also demonstrate how these tools can be easily adapted to add value to research environments. Additionally, this progress represents a step toward interoperability in automation, data, and models and, consequently, bringing digital engineering tools to data-starved high-mix low-volume manufacturing.