Abstracts

“Environmental Advantages of an Additively Manufactured Micro-Turbine Engine” by Mr. Michael Froning and Mr. Kelsey Snively (WP20-5083)

Micro-turbine engines, which have both air and ground power applications, are in growing demand. There is also a need across the Department of Defense (DoD) for power plants that yield a reduced environmental impact. The Air Force Life Cycle Management Center Product Support Engineering Division and University of Dayton Research Institute team utilized a commercially available EOS M290 additive manufacturing (AM) machine to build a newly designed micro-turbine, employing a powder bed fusion and direct metal laser melting technology that uses lasers to melt ultra-thin layers of metal powder to build a three-dimensional part. Improvements in engine efficiency were identified via use of computational fluid dynamics modeling and simulation to determine optimized engine geometry that is also well suited for the AM process. Optimizations of the engine compressor, combustor, and turbine stages were performed. The performance of each stage was demonstrated via printing and testing of the AM engine. The AM engine was successfully tested at its idle condition and up to roughly 50% of its anticipated maximum speed. Testing at these conditions has been shown to be stable and the engine’s startup procedure is repeatable. Manufacturing cost benefits were demonstrated through use of cost benefit analysis tools and comparison to costs of similar commercially available engines. Likewise, environmental advantages related to the manufacturing of the AM engine were demonstrated via environmental studies conducted on the AM process and comparison to traditional engine manufacturing methods.

“From Waste Steel to Weapons: Additive Manufacturing Enabled Agile Manufacturing” by Dr. Diran Apelian and Dr. Jianyu Liang (WP18-1176)

This project was aimed to help address the issue of ferrous waste in forward operating bases (FOBs) (ferrous waste comprises over 60% of metal wastes). The project focused on developing an AM-enabled investment casting process using ferrous scrap from FOBs. It involved characterizing ferrous waste and creating a database for recycling. A model was developed for selecting scrap and making target alloys. The use of stereolithography printed patterns replaced traditional wax patterns, enhancing manufacturing flexibility. A ceramic shell-making process using zirconium silicate-based slurry and zircon sand was established, with optimized procedures for shell fabrication and stereo lithography apparatus (SLA) pattern removal. MagmaSoft aided in casting tree design. A mobile foundry system, comprising three containers, was designed for rapid part manufacturing in field conditions. This system included casting facilities and inspection equipment, with simulations in ANSYS ensuring safety. A list of necessary microgrid systems and instruments for the foundry was compiled with supplier details. For post-treatment, data-driven tools were developed, including an artificial neural network model to analyze the relationship between steel compositions and various mechanical properties. In summary, the project successfully established an AM-enabled investment casting process using FOB ferrous scrap, introduced a mobile foundry system, and developed tools for post-treatment analysis. These advancements lay the groundwork for further research in this field.

Speaker Biographies

Mr. Michael Froning is a technical director in the sustainment technology transition branch at the Air Force Life Cycle Management Center, Wright-Patterson Air Force Base, Dayton, Ohio. Mr. Froning has 29 years of industry experience working for General Motors and Delphi Automotive serving in multiple senior level positions. He has spent the last 15 years working for the Air Force at Wright-Patterson. He currently leads multiple new technologies initiatives involving process tooling improvements, removal of paints and coatings, additive manufacturing, and cold spray repairs. Mr. Froning has served as principal investigator on several ESTCP projects focused on environmentally friendly technologies for U.S. Air Force maintenance and sustainment applications, which received several prestigious awards (ESTCP 2022 Weapon Systems and Platforms Project of the Year [WP18-5031, Environmentally Friendly Paint Removal from Military Components], CTMA 2023 Technical Competition and ODASD-MR Award for Outstanding Technological Achievement in the Field of Maintenance and Sustainment [WP22-7328, Ultrasonically Activated De-Paint Technology], 1st Place at Technical Competition Advanced Concepts and Members’ Choice Award at Additive Manufacturing Users Group, AMUG 2023 conference [WP20-5083, Additively Manufactured (AM) Micro-Turbine Engine]). Mr. Froning received a bachelor’s degree in mechanical engineering from the University of Dayton, a master’s degree in materials science from the University of Dayton, and a graduate degree of engineering in metallurgy from the University of Florida.

Mr. Kelsey Snively is a senior additive manufacturing engineer in the sustainment technology transition division at the University of Dayton Research Institute (UDRI). His professional experience includes time spent in multiple industries including automotive, aerospace, and additive manufacturing (AM), including 6 years spent working in metal AM, with the last 4 years spent at UDRI developing metal AM applications for the U.S. Air Force. Examples include the use of metal AM in structural aircraft components, wind tunnel models, and small engine applications. He served as the technical lead for ESTCP Program WP20-5083, the development of an AM micro-turbine engine. The program garnered national attention for its unique use of AM, earning two first place awards in the technical competition at the 2023 Additive Manufacturing Users Group (AMUG) conference (Advanced Concepts Award and Members’ Choice Award). Mr. Snively received a bachelor’s degree in mechanical engineering from the University of Dayton and a master’s degree in mechanical engineering from Purdue University.

Dr. Diran Apelian is a distinguished professor of materials science and engineering at the University of California, Irvine (UCI) where he also serves as the strategy officer for the Samueli School of Engineering and the director of the Advanced Casting Research Center. He is provost emeritus of Worcester Polytechnic Institute (WPI) in Massachusetts. Dr. Apelian's career began at Bethlehem Steel's Homer Research Laboratories, followed by a faculty position at Drexel University in 1976, where he became head of the Department of Materials Engineering, associate dean, and vice provost. In 1990, he joined WPI as provost, later founding the Metal Processing Institute there in 1996. He joined UCI’s faculty in July 2019. A recipient of numerous honors and awards, Dr. Apelian has over 700 publications and 21 patents. He has founded six companies, including Materials Strategies and Battery Resourcers. He also served in various leadership roles, including as president of TMS (2008/2009), chair of the ASM Educational Foundation Board (2016-2018), and founding editor of the Journal of Sustainable Metallurgy. He is a fellow of TMS, ASM, and APMI, and a member of several national and international academies, including the National Academy of Engineering. He received the 2016 Bernard Gordon Prize for Innovation in Engineering Education and was recognized as innovator of the year at WPI in 2018 and UCI in 2020. Dr. Apelian received a bachelor’s degree in metallurgical engineering from Drexel University in 1968 and a doctoral degree in materials science and engineering from MIT in 1972.

Dr. Jianyu Liang is a professor of mechanical and materials engineering at Worcester Polytechnic Institute (WPI) and director of the materials and manufacturing engineering program. She has affiliated appointments in fire protection engineering, civil and environmental engineering, as well as chemical engineering at WPI. Her career included positions as guest researcher at the Army Research Laboratory (2013 - 2014) and as visiting professor at Brown University's School of Engineering in 2023. Since joining WPI in 2004, Dr. Liang's research has focused on energy and sustainability, covering areas such as lithium ion batteries, fuel cells, and recycling and repurposing waste materials. Her work has attracted funding from National Science Foundation, NASA, the Department of Defense, the Department of Education, and various industrial partners. She has co-authored or authored 92 technical papers and book chapters and delivered over 150 technical presentations. Dr. Liang received a bachelor’s degree from Central South University in China, a master’s degree from Central South University in China, and a doctoral degree from Brown University.