Additive Manufacturing: Alternative Processes (Beyond the Beam): Emerging Additive Processes
Sponsored by: TMS Materials Processing and Manufacturing Division, TMS: Additive Manufacturing Committee, TMS: Powder Materials Committee
Program Organizers: Paul Prichard, Kennametal Inc.; Matthew Dunstan, US Army Research Laboratory; Peeyush Nandwana, Oak Ridge National Laboratory; Nihan Tuncer, Desktop Metal; James Paramore, Texas A&M University

Tuesday 8:30 AM
February 25, 2020
Room: 7A
Location: San Diego Convention Ctr

Session Chair: Nihan Tuncer, Desktop Metals


8:30 AM  
Characterization of 17-4 PH Processed via Bound Metal Deposition (BMD): Alexander Watson1; John Belding1; Brett Ellis1; 1University of Maine
    Advancements in Selective Laser Sintering (SLS) and Electron Beam Melting (EBM) additive manufacturing (AM) of metals have led to reduced lead times, increased geometric freedom, and enhanced part functionality; however, SLS and EBM are plagued by relatively high capital and operational costs. With costs approximately 60% to 80% less than SLS or EBM, Bound Metal Deposition (BMD) is a new AM process in which a metal powder-binder composite material is printed sequentially in layers, debound, and sintered to form a 96%- to 99%-dense part. This work characterizes the mechanical properties of 17-4 PH stainless steel material within a BMD process. Mechanical characterization includes process-, print-orientation-, and geometry-dependent shrinkage; monotonic, quasi-static tensile data (e.g., modulus, yield strength, ultimate strength, and ductility); hardness; and microstructures. This work is significant in that characterization studies are required to understand process-structure-properties relations for the BMD manufacturing process prior to realizing commercial opportunities.

8:50 AM  
Development of Tuned Composites Based on Metallic Particles for Advanced 3D-printing by Fused Deposition Modeling: Ester Palmero1; Daniel Casaleiz1; Javier de Vicente1; Juan Hernández-Vicen2; Silvia López-Vidal2; Emilio Ramiro2; Alberto Bollero1; 1IMDEA Nanoscience; 2RAMEM S.A.
     The collaboration between research centers and industry is of large importance to advance in the development of a technology that, in spite of its youth, is experiencing vertiginous achievements in many different technological sectors. This study will show first the possibility of synthesizing composites (aluminum and stainless-steel gas-atomized particles/polymer) with tuned filling factor (metal FF=50-90%) by solution casting. Extrusion of these composites has allowed the fabrication of flexible filaments for 3D-printing by Fused Deposition Modeling. We will also show that magnetometry is a time-saving and accurate technique for quantifying the FF and quality (possible deterioration during processing) of magnetic composites and filaments (e.g. magnetic steel-based) [1,2]. Suitability for 3D-printing has been confirmed by printing metal-based pieces with different shapes[1], demonstrating the potential applicability of this methodology in technological sectors. [1] Palmero, Compos. Part A Appl. Sci. Manuf. 124, 105497 (2019). [2] Palmero, Sci. Technol. Adv. Mater. 19, 465 (2018).

9:10 AM  
Additive Manufacturing of High-value Metal Parts Through Shaping-debinding-sintering: Peter Felfer1; Yvonne Thompson1; Joamin Gonzalez - Gutierrez2; Christian Kukla2; 1Fau Erlangen-Nurnberg; 2Montanuniversität Leoben
    Additive manufacturing through shaping-debinding-sintering of metal filled polymer materials is a great alternative to beam-based methods for smaller parts. It involves the shaping of a part through fused filament deposition of a highly filled filament (fillgrade > 55%), which can be done using consumer-grade 3D printers. This is followed by a step where the main binder component is removed by a solvent, creating a green body. The green body, held together by a “backbone” polymer is then treated in a furnace, where the backbone component is thermally removed followed by a sintering step producing the solid part. This process is generally lower cost, uses simple equipment and does not involve the handling of metal powders, making it ideal for distributed manufacturing. In this talk, we will show the application of this technique to the manufacturing of parts from high-value, high performance materials, including titanium, copper and superalloys (A718).

9:30 AM  
Topology Optimization-based Design Customized for Alternative AM Processes: Julia Carroll1; Hak Yong Lee1; James Guest1; Reza Behrou1; 1Johns Hopkins University
    Topology optimization (TO) is a powerful tool capable of generating designs for components and architected materials that offer significant performance gains and mass reductions over existing concepts. Although topology optimization is particularly well-suited to exploit the geometric freedom provided by additive manufacturing (AM), it is a missed opportunity to use these technologies in isolation. Rather, TO and AM must be fully integrated to achieve maximal benefits, such as maximal performance gains and reduced design cycle time, production (and post-production) time, and cost. This talk will discuss a requirements-driven TO framework that is tailorable to the specific capabilities of a manufacturing process. In particular, we will focus on TO algorithms specifically customized to leverage alternative AM processes, including material jetting and fiber-extruded printing, among others, and demonstrate how the details of the AM process must be considered in the design process to fully leverage the capabilities of additive manufacturing.

9:50 AM Break

10:10 AM  
On the Interaction and Forms of Adhesion Between Various Substrate Materials and Molten Metal Droplets Produced by the Drop-on-demand Technology Metal Jet: Nesma Aboulkhair1; Marco Simonelli1; Mark East1; Richard Hague1; 1University of Nottingham
    The focus in metal additive manufacturing has mostly been on the powder-bed fusion and direct-energy-deposition techniques. Despite the amazing capabilities offered by these technologies and the significantly higher degrees of freedom that enable achieving greater shape complexities compared to conventional manufacturing, they have some limitations when it comes to multi-material printing for multi-functionality. This is besides the health and safety issues related to powder use and handling. In this work, we introduce a novel bespoke high-temperature metal multi-material droplet-on-demand technology, referred to as “MetalJet”. The system was validated for low (Sn) and high (Ag and Cu) temperature pure metals showing that it can additively manufacture complex structures from 70 micro-meter sized droplets drop-by-drop by employing Lorentz force. MetalJet was used to jet pure metals on a range of metallic and dielectric substrates. The drop-to-drop and drop-to-substrate interfaces were examined using a range of microstructural and mechanical characterisation techniques.

10:30 AM  
3D-printing Bulk Metallic Glass Alloys with Ultrasonic Additive Manufacturing: Adam Hehr1; Mark Norfolk1; Evelina Vogli2; Scott Roberts3; 1Fabrisonic LLC; 2LM Group Holdings, Inc.; 3Jet Propulsion Laboratory, California Institute of Technology
    Ultrasonic Additive Manufacturing (UAM), a 3D metal printing technology, uses ultrasonic energy and pressure to produce metallurgical bonds between layers of metal foils with minimal heating to the welded materials. The lack of heat input enables joining of dissimilar metals and temperature sensitive foils together, e.g., joining of bulk metallic glass or amorphous foils. This study discusses the development and evaluation of multiple bulk metallic glass alloys joined together using the UAM process. Evaluation includes qualitative testing, microscopy, x-ray diffraction, electron backscatter diffraction, and differential scanning calorimetry.