University, NSWC Dahlgren partnership seeks to further 3-D manufacturing research, tech
CHARLOTTESVILLE, Va. Students and professors at the University of Virginia (UVA) and engineers and scientists from the Naval Surface Warfare Center Dahlgren Division (NSWCDD) are working together through the Naval Engineering Education Consortium (NEEC) to develop a better understanding of the capabilities and limitations of additive manufacturing (3-D printing).
The objective of the NSWCDD-University of Virginia project -- instituted in 2016 -- is to develop quantitative connections among materials process parameters, microstructure, and properties, all of which are necessary for qualification of additively manufactured parts for use in critical load-bearing components.
The U.S. Navy has identified additive manufacturing as an emergent need for the Navy, in the belief that the technological capability is an alternative to existing manufacturing technologies based on casting, forging, and machining parts. Many view it as a critical means of providing rapid prototyping, dimensional restoration, and in-service replacement of legacy components that are no longer being made.
“The research that the University of Virginia is conducting is an important examination of the microstructure and mechanical properties of alloys relevant to the Navy produced by state-of-the-art additive manufacturing techniques,” said Ricky Moore, an NSWCDD engineer and mentor to the students. “Understanding these properties is paramount as the Navy begins to design, develop, produce, and field components and systems produced with additive manufacturing to improve performance and availability of systems in the fleet. Without it, much of the promise of additive manufacturing will be out of reach."
University of Virginia professor Dr. Sean Agnew said of the project: "Our collaboration has opened the door to the fascinating world of additive manufacturing of metals. The results we have been able to collect in this study have confirmed that the combined mechanical properties – the strength and ductility of 3-D printed 316L stainless steel – can be far superior to incumbent wrought processed material. Not only did we confirm these properties, we also were able to develop structure-property relationships to establish the origin of the enhanced strength. Surprisingly, a higher number of defects in the microstructure actually impart improved properties. The fact that the ductility remains high is still surprising and will serve as the basis for future research. We have been able to parlay this initial experience to build a broader network of collaborators that spans research institutes across the United States and Australia."