Active research areas
Fundamental powder metallurgy: modeling & Advanced characterization
This research is a focal point of the Cote Research Lab, based upon the group's vast knowledge of and expertise in modeling and characterizing powder materials. Utilizing advanced thermodynamic and kinetic modeling coupled with many experimental techniques - including electron microscopy, ion polishing, and powder rheology, to name a few - we are able to gain insights into the inner workings of nearly any powder material on a chemical and physical basis.
Figure: Scanning electron microscopy (SEM) image of Inconel powder.
Figure: An SEM Micrograph of a single Al 6061 particle deposit (top-down perspective) is overlayed onto a larger SEM micrograph of a cross-sectioned Al 6061 single particle deposit prepared by plasma FIB.
Development for Cold Spray Processing
Cold spray processing involves research efforts across domains. A couple areas we focus on are robotic path planning and powder recyclability. Watch the video to learn about our cold spray research!
Figure: Materials science tetrahedron representing the relationships between a material's structure, processing, performance, and properties. These relationships are crucial to the materials science of additive manufacturing, as explored by the Cote Resesarch Lab.
Structure-processing-properties-performance Linkages
The Cote Research Lab work embodies the Structure-Processing-Properties-Performance tetrahedron in all of our research. One example is in our Through-Process Models for predicting the properties of advanced additive manufacturing techniques (e.g. cold spray and wire arc AM) where we simulate the microstructure of the feedstock material and follow it's properties and performance as it undergoes various processing techniques.
Micro- and nano-scale material property evaluation
The Cote Research Lab applies and develops novel modes of inspecting multi-scale mechanical properties of materials to assess the mechanical behavior of materials across length scales, from nano-, micro- and macro-scale.
The instruments used to collect such data include nanoindentation at the nano-scale, an indentation plastometer at micro-scale, and a particle compression tester at macro-scale.
Figure: Continued confocal analysis of pile-up associated with nano-indented Al 6061 powder. (a) presents five indentation imprints and their respective degree of pile-up that are associated with the graphical height versus spacing data presented in (b).
Computational thermodynamic, kinetic, & rapid Solidification simulations
Computational thermodynamic, kinetic, and solidification modeling provide a foundation and guidance for nearly every research area of our group. It provides valuable insight into the material behavior and properties.
Figure: Variation of the prediction of the equilibrium alpha phase in Al 6061 with a content variation of iron according to the legend provided. Two vertically dashed lines were superimposed upon the phase fraction versus temperature curves at 25 and 500 °C, respectively, to identify the temperatures associated with the embedded demonstration of two Elemental Impact Factors.
Figure: Linear Pearson Correlation Matrix. This shows the covariance between the features of the particles. The clustered groups of the same color such as the ones in the top left quadrant, reveal a high degree of correlation between the variables.
This research is based on an interdisciplinary effort between the Cote Research Group and Data Science Professor Rodica Neamtu's research group. We use advanced data science techniques to shed light on new insights into materials science and advanced manufacturing. These techniques have provided eye-opening observations that would have been overlooked without this perspective.
Antimicrobial cold spray coatings
Copper has been exploited for its antimicrobial properties for centuries. We explore the effects of cold spraying copper and other materials to increase antimicrobial efficacy as well as providing a flexible application process. Application to SARS viruses, such as COVID-19 are also explored.
See our publications on the topic:
B. Sousa, D. L. Cote, “Antimicrobial Copper Cold Spray Coatings and SARS-CoV-2 Surface Inactivation,” MRS Advances. Vol 5(56), 2873-2880. December 2020. https://doi.org/10.1557/adv.2020.366
B. Sousa, M. Gleason, D. L. Cote, "Prevention of Contact Transmission of SARS-CoV-2 with Copper Cold Spray Coatings," Journal of Diagnostic Techniques and Biomedical Analysis, Volume 9(3) pp 232. September 2020. DOI: 10.37532/jdtba
Wire Arc Directed energy deposition (Wire arc ded)
We explore the feedstock wire used in the high deposition rate directed energy deposition (DED) wire arc additive manufacturing process.