Seminar: Application of Quantitative 3-D Imaging to Better Understand the Relationships between Chemical Formulation, Morphological Characteristics and Physical Properties of Materials
Brian Patterson
Polymer and Coating Group, Los Alamos National Laboratory
Friday, September 19, 2014
1:30 p.m.
John W. Schwada (SCOB) 250, Tempe Campus [map]
Abstract:
X-ray computed tomography (CT), is an indispensable tool for materials development and characterization. With this technique, 3-D images of a material are collected, non- destructively, providing a probe into its internal 3-D structure. This provides a better understanding of its manufactured morphology, after-experiment morphology, and even the morphological changes during the experiment. This presentation will focus on four recent topics on the use of X- ray CT and confocal micro X-ray fluorescence within the Materials Science and Technology Division at Los Alamos National Laboratory to answer a variety of materials challenges. These challenges include understanding metal damage and solidification, mechanical response within polymer foams, and quantification of embedded metallic layers. On top of these challenges, much of our research has focused on improving the robustness of CT measurements and making them more quantitative. Probing questions such as, “How many radiographs do I really need to acquire?”, and “What resolution do I need so that the statistics are related to the object and are not skewed by the number of voxels within the object?” provides a foundation to answer these materials science questions with more confidence. CT provides an avenue for the quantification of morphological structure of solidified materials. Measuring features on the micrometer scale can be used to understand processing history and continues to show that sample preparation is still key. Additionally, CT can be used to relate polymer foam synthesis to its morphological structure, and then to its mechanical performance. For blown polymeric foams, in which the foaming process is stochastic, studies relating morphological structure to performance are especially difficult. In-situ mechanical performance measurements of these polymer foams, as well as foams made through additive manufacturing, while they are imaged 3-D using laboratory and synchrotron based X-ray tomography, opens up a variety of research avenues to better understand mechanical performance. Finally, coupling CT with confocal micro X-ray fluorescence spectroscopy, a 3-D elementally-specific spectroscopic technique, opens up other venues for rapid materials screening and elemental identification.
Biosketch:
Brian M. Patterson is an R&D Scientist and Team leader of the Characterization and Forensics team in the Polymers and Coatings Group, MST-7. He graduated from the University of Toledo with a Bachelor of Education, teaching high school science for two years before entering graduate school. He received a Ph.D. in Analytical Chemistry from Miami University, Oxford, OH in 2004 under the direction of Andre’ J. Sommer developing techniques in infrared micro- spectroscopy. He joined the Chemistry Division at Los Alamos National Laboratory under the direction George J. Havrilla as a post-doctoral researcher in 2004 working in the area of micro X-ray fluorescence and FT-IR imaging. Brian was converted to a LANL staff member in 2006. Brian’s expertise and research interests are in materials analysis using X-rays; specifically micro- and nano-scale X-ray computed tomography and micro X-ray fluorescence. Using these techniques he answers a variety of materials science questions relating to: high explosives, polymer foams, aerogels, carbon fiber composites, damaged materials, and low density materials examining defects (intentional and unintentional), voids, and the distribution of their component materials. He specializes in morphological structure quantification, in-situ dynamic measurements and overlaying imaging techniques to synergistically answer questions in 2D and 3-D. He also currently serves on the editorial board of Microscopy Today.
Please contact Durella O’Donnell at Durella.ODonnell@asu.edu for more information, or if you would like to meet with Brian Patterson while he is on campus.
