ERI: Mechanistic Insights into Enhancing Uniform Dispersion of Micro-scale Ceramic Reinforcements in Directed Energy Deposition of Metal Matrix Composites

Ceramic particle-reinforced metal matrix composites (MMCs) have attracted wide interest across multiple industries because they combine the ductility and toughness of metals with the hardness, stiffness, and thermal stability of ceramics. In recent years, additive manufacturing (AM) has emerged for producing MMCs with complex geometries and functionally graded structures. Among AM technologies, directed energy deposition (DED) offers exceptional flexibility in material feedstock control, making it suitable for fabricating MMCs ranging from protective coatings to complex bulk components. Although DED has been successfully employed to manufacture a wide range of ceramic particle-reinforced MMC systems, achieving uniform particle dispersion remains a major scientific and technological challenge. Reinforcement particles often segregate due to density mismatch and complex melt-pool fluid flow, resulting in heterogeneous microstructures and reduced mechanical reliability. This Engineering Research Initiation (ERI) project aims to uncover the fundamental mechanisms governing three-dimensional (3D) particle dispersion during DED and to identify manufacturing conditions that promote uniform particle distribution. The outcomes will advance the scientific foundation of additive manufacturing and strengthen the United States’ capability to produce high-performance materials for critical industries including aerospace, energy, and defense. This research will also contribute to education and workforce development by involving undergraduate and graduate students in research activities, integrating additive manufacturing experiments into engineering courses, and engaging K-12 students through outreach programs. The technical objective of this work is to establish a mechanism-guided framework for controlling the three-dimensional dispersion of micro-scale ceramic reinforcements in directed energy deposition of metal matrix composites. The research integrates controlled experiments, advanced characterization, and multiphysics modeling to reveal the relationships among processing conditions, particle transport mechanisms, and resulting mechanical properties. Specifically, this work will first quantify how process parameters influence both local (short-range clustering) and global dispersion uniformity in three-dimension. Second, the dominant forces governing particle transport within the melt pool will be elucidated using a validated multiphase computational fluid dynamics (CFD) model. Third, the relationship between dispersion uniformity and mechanical performance will be established. By linking process parameters to particle transport mechanisms and material performance, this research will provide predictive guidelines for achieving uniform reinforcement dispersion in DED-built MMCs. The results will advance the fundamental understanding of particle behavior in additive manufacturing and enable more reliable fabrication of high-performance composite components. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria. NSF Award ID: 2553094 | Program: 01002627DB NSF RESEARCH & RELATED ACTIVIT | Principal Investigator: Yue Zhou | Institution: Embry-Riddle Aeronautical University, DAYTONA BEACH, FL | Award Amount: $200,000 View on NSF Award Search: https://www.nsf.gov/awardsearch/show-award/?AWD_ID=2553094 View on Research.gov: https://www.research.gov/awardapi-service/v1/awards/2553094.html