2023 Annual International Solid Freeform Fabrication Symposium (SFF Symp 2023): Economics of AM
Program Organizers: Joseph Beaman, University of Texas at Austin
Tuesday 2:40 PM
August 15, 2023
Room: Salon G
Location: Hilton Austin
Session Chair: Paul Hooper, Imperial College London
2:40 PM
Anticounterfeiting Signatures for Additively Manufactured Parts via Electromechanical Impedance Measurements: Nathan Raeker-Jordan1; Christopher Williams1; 1Virginia Tech
Additive manufacturing (AM) is increasingly used to create complex end-use parts for critical systems across a distributed supply chain. However, these parts are at risk of counterfeiting by a capable attacker, either by using stolen digital designs or reverse engineering. Extrinsic part identification such as barcodes and ID numbers placed onto part surfaces can similarly be defeated. In this work, the authors explore the use of electromechanical impedance (EMI) measurements as a physically unclonable function for identifying printed parts via an attached piezoelectric sensor-actuator. As the EMI response is intrinsic to the geometry and material properties of a part, the natural variation in AM processes causes distinct EMI responses for nominally identical parts. This ability for EMI responses to serve as a “digital fingerprint” is evaluated across several AM processes, and is shown to be capable of differentiating between unique parts produced using binder jetting, material jetting, and material extrusion.
3:00 PM
Streaming in Additive Manufacturing: Analyzing the Impact on the Powder Bed Fusion of Metals Process Chain: Moritz Kolter1; Johannes Schleifenbaum1; 1RWTH Aachen University - Digital Additive Production DAP
Streaming is a popular concept in the music and movie industry and has helped solve problems related to file distribution, storage capacity and intellectual property protection. In recent years, streaming has also become a research topic for the manufacturing sector, e.g., to collect data for predictive maintenance, advanced machine control concepts, or over-the-air updates. After initial studies have investigated the feasibility of streaming for additive manufacturing technologies, the question is how streaming will affect the process chain. In the music and movie industries, new business models and customer experiences have been created, leading to billion-dollar businesses and the creation of companies such as Netflix and Sportify. In this paper, the impact of streaming on the additive process chain is analyzed using Laser Powder Bed Fusion (L-PBF). The process chain is modeled for different scenarios and its potential impact on the supply chain and future research opportunities are outlined.
3:20 PM
Designing for Circular Economies: Creating Impact from Local Plastic Waste using Off-grid Containerized 3D Printers & Practice Based Learning: Doug Sassaman1; Chris Hong1; Sofia Valdez1; Yael Glazer1; William Stockton2; Michael Webber1; Charlotte Craff3; Samantha Snabes3; Aziz Ahmed4; Leela Kempton4; Richard Yang5; Tosin Famakinwa5; Jojibabu Panta5; Phan Nguyen5; Britney Blann2; Carolyn Seepersad1; 1University of Texas Austin; 2Austin Habitat for Humanity; 3re:3D, Inc.; 4University of Wollongong; 5Western Sydney University
This project aims to create sustainable and user-customizable home goods from local waste plastic, and comprises four thrusts: 3D printing from waste with fused granular fabrication (FGF), life cycle analysis (LCA) of the FGF process, a minimum footprint mobile recycling and 3D printing system (Gigalab), and design in collaboration with end users. The FGF technology allows direct printing from waste plastic and was experimentally and numerically evaluated for part performance and microstructure. The Gigalab minimizes transportation and carbon footprint, and an LCA informed the design of the next generation system. The interactive framework based on topology optimization and deep learning enables users to design functional and aesthetically pleasing home furnishings while ensuring sustainability and structural integrity. The project is a case study with Austin Habitat for Humanity ReStores, using waste plastic from their reStore, involving their customers as end users, manufacturing and selling the printed goods at the ReStores.
3:40 PM
How Good is Good Enough? The Economics of In-process Monitoring in AM: Paul Hooper1; Harry de Winton1; 1Imperial College London
It is widely recognised that in-process monitoring of additive manufacturing (AM) processes is crucial to providing robust quality assurance procedures, leading to increased acceptance of AM parts in critical applications. Although some of the gains of in-process monitoring are intangible, there are clear economic arguments that can be made to quantify the benefits of a system for different applications. This works aims to answer the question: what detection performance needs to achieved for an in-process system to be cost effect? We look at a range of industry case studies across the aerospace and nuclear industries that cover different production volumes, part costings and inspection requirements. Different costs models are analysed, capturing a monitoring system’s ability to stop production of a defective part or replace conventional non-destructive evaluation processes. Total production savings from implementing in-process monitoring range from 0% to 40% in the case studies presented.
4:00 PM
Development of High Filled Bio-based Composites for Sustainable, Low-cost Feedstock: Processing Effects on Porosity and Fiber Alignment: Katie Copenhaver1; Meghan Lamm1; Amber Hubbard1; 1Oak Ridge National Laboratory
PLA composite with a high loading of bio-based fibers was developed using a combination of high-AR wood pulp and low-AR wood flour along with viscosity modifiers to maximize mechanical performance, maintain processability, and lower the cost and embodied energy of the resulting AM feedstock. An optimized composite formulation was scaled up to produce pellet feedstock using twin screw extrusion, and materials were compression and injection molded to investigate the effect of fiber alignment on material performance. The feedstock was then printed on the Big Area Additive Manufacturing system at Oak Ridge National Laboratory. Print parameters including temperature gradients, screw and gantry speeds, layer times, and nozzle designs were varied to minimize sharkskinning, warpage, and porosity of the final parts. A strong effect of the nozzle size on the resulting porosity was observed, and consistent trends between decreasing porosity, increasing fiber alignment, and increasing mechanical performance were identified after printing with different nozzles, compression molding, and injection molding.