Understanding the Processing-Microstructure-Property Relationships of Additively Manufactured Parts during Direct Metal Laser Sintering Processes: Multi-scale Modeling and Experimental Characterizatio
Abstract
Additive manufacturing is a rapid prototyping technology for the development of innovative metallic and composite materials. In particular, the direct metal laser sintering (DMLS) based AM process has become increasingly popular due to the fact that it can avoid the balling phenomenon and produce the final densified parts do not need post-processing. However, the DMLS processes are extremely complex and slight variation of operational parameters can cause great uncertainty on manufactured parts to meet product performance. As a result, the product performance characterization and validation are currently driven primarily by expensive and time-consuming trial-and-error approaches, which are increasingly becoming a norm in the production floor due to the inadequacies of robust process design guidelines and predictive tools that are available today. The lack of performance predictability and understanding of DMLS based AM process and parameters, especially during the build-up process, could reduce the level of confidence expected with state-of-the-art AM products. Therefore, developing high fidelity and suitable modeling tools that can predict the Processing-Microstructure-Property relationships of DMLS produced components cannot be overemphasized for its important role. The overarching goals of this proposal are to: I. Advance the current understanding of multiscale and multiphase energy transport processes during AM; II. Provide enabling technologies for advanced design and future applications in Naval systems; III. Enhance UDCÕs existing research capabilities and to broaden the participation of underrepresented minority and female students (URMs) at UDC and local communities in support of national defense. Specifically, four interwoven activities will be carried out here: First, the PIs will investigate the correlation between the AM powder microstructure and the mechanical properties of post-build products. Secondly, the PIs will study the impact of build process parameters on the mechanical properties of post-build products through in-situ melting pool characterization and thermal gradient measurement. Thirdly, the PIs will carry out the AM data feature selection and analysis of high dimensional and highly overlapped AM data using hybrid binary particle swarm optimization (BPSO) and evolutionary algorithm (EA) based method. Fourthly, the PIs will develop and validate a high-fidelity multi-scale and multi-physics process model that can be used to optimize the DMLS build process. Meanwhile, this project aligns well with UDCÕs strategical plan 2022 via engaging students in interdisciplinary research, offering experiential manufacturing experience to UDC and local high school students and teachers, and broadening the participation of USM groups in STEM disciplines, particularly the areas pertaining to Navy-unique technical interests. These research and associated outreach activities proposed here will recruit students, primarily from underserved categories from high schools and community colleges to attract and retain diverse talent in STEM. It will enable the infusion of AM in our undergraduate programs from the freshman to senior level. Students will participate in experiential learning by directly working on the research projects proposed here or by working on related AM topics with UDC faculty or collaborator institutes. This project will assist UDCÕs newly approved doctoral program in the School of Engineering, and it will directly benefit from graduate students as they will be involved in the proposed research and course activities. This project will also help us to enable and foster collaborations and partnerships with highly resourceful institutions and agencies within the Washington metropolitan area.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Aug 31, 2020
- Source ID
- W911NF2010274
Entities
People
- Jiajun Xu
Organizations
- Army Contracting Command
- Office of the Secretary of Defense
- University of the District of Columbia