Multiscale Modeling and Characterization of Ceramic Matrix Composites
Abstract: The Department of the Air Force is increasingly challenging the art of what is possible in order to compete with potential adversaries who are advancing their technology rapidly to counter the current established international order. Materials are at the heart of many current technology concept limitations, particularly those that operate in extreme environments such as future hypersonic vehicles or orbiting space systems. Here we will discuss several ongoing efforts to increase our ability to characterize and predict composite performance in application relevant extreme environments. For example, machine learning approaches are being employed to automate the classification of features in composite microstructures. This is allowing researchers to detect and track individual fibers in three-dimensional x-ray CT datasets to characterize local microstructural variation and damage. We are also employing machine learning to better understand damage initiation and propagation in composite structures at the microscale. Here, a reduce-order, data-driven, probabilistic predictive model to quantify damage initiation in CMCs at pertinent lengths scales was developed. This data driven framework was developed to incorporate microstructural features using a statistical representation and using them to predict matrix crack initiation and propagation. Additional modeling approaches such as continuum damage and phase field fracture modeling approaches are also being leveraged to model the physics of microstructure dependent damage progression. Such approaches have to potential to better inform engineers during the design, certification and sustainment of complex systems. The calibration and application of these models to currently produced relevant CMC systems will be discussed. Finally, perspectives on future needs and research directions in these areas will be addressed.
Dr. Craig Paul Przybyla is currently the Research Team Leader of the Composite Performance Team at the Materials and Manufacturing Directorate, Air Force Research Laboratory (AFRL), Wright-Patterson Air Force Base, Ohio where he leads a team of researchers focused on the performance characterization and prediction of advanced polymer and ceramic matrix composites for aerospace applications. His specific area of specialty includes the performance characterization and modeling of composites in extreme environments. Prior to that assignment, he was a Materials Research Engineer at the Office National d'Etudes et de Recherches Aérospatiales (ONERA) in Châtillon, France as part of the Engineering and Scientist Exchange program between the United States Department of Defense and French Ministry of Defense from 2019-2021. In that position, Dr. Przybyla collaborated with our French allies on the utilization of advanced numerical techniques to predict the performance of high temperature composites as a function of the stochastic material microstructure in application relevant environments.
Additional previous assignments include serving the Research Team Leader of the Composites Performance Team between 2015 and 2019 and a Materials Engineer from 2010 to 2014 where he worked as a Research Engineer and subject matter expert for performance characterization and modeling of ceramic matrix composites for hot section components in gas turbine engines and/or thermal protection systems for hypersonic vehicles. Dr. Przybyla first joined the federal civil service in 2007 as a Co-op student in the Metals Branch at AFRL where he developed physics-based performance models to predict fatigue crack initiation in Titanium alloys and Nickel base super alloys.
In Nov. 2010 to April 2011, Dr. Przybyla was sponsored by the Air Force Research Laboratory to work as a Visiting Materials Engineer at GE Aviation in Evendale, Ohio. In this assignment, He worked with GE engineers on the performance characterization of the new HiPerComp® Silicon Carbide continuous fiber reinforced Silicon Carbide matrix composites that were developed for next generation gas turbine engine hot section combustor liners, shrouds, vanes and blades for both commercial and military gas turbine engines (e.g., LEAP® Engine). Since Sept. 2013, Dr. Przybyla has also been working as an adjunct professor at Wright State University, Dayton, Ohio, in the Raj Soin College of Business. In this position, he teaches undergraduate business statistics, quantitative business modeling, and operations management courses.
2004 Bachelor of Science, Mechanical Engineering, Brigham Young University, Provo, Utah
2005 Master of Science, Mechanical Engineering, Brigham Young University, Provo, Utah
2010 Doctor of Philosophy, Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Ga.
1. May 2008 – February 2010 Student Trainee, Metals Branch, Materials and Manufacturing Directorate, Air Force Research Laboratory (AFRL), Wright-Patterson Air Force Base (AFB), Ohio
2. February 2010 – September 2012 Materials Engineer, Ceramics Branch, Materials and Manufacturing Directorate, AFRL, Wirght Patterson AFB, Ohio
3. November 2010 – April 2011 Visiting Materials Engineer, GE Aviation, Evendale, Ohio
4. September 2012 – January 2015 Materials Engineer, Composites Branch, Materials and Manufacturing Directorate, AFRL, Wright Patterson AFB, Ohio
5. January 2015 – January 2019 Research Team Leader, Senior Materials Engineer, Composites Branch, Materials and Manufacturing Directorate, AFRL, Wright-Patterson AFB, Ohio
6. February 2019 – July 2019 – Defense Language Institute (DLI), Washington DC -- French
7. August 2019 – August 2021, Materials Research Engineer (Engineering Scientist and Exchange Program), Office National d'Etudes et de Recherches Aérospatiales, Châtillon, France
8. September 2013 – Present Adjunct Professor, Raj Soin College of Business, Wright State University, Dayton, Ohio
9. August 2021 – Present Research Team Leader, Senior Materials Engineer, Composites Branch, Materials and Manufacturing Directorate, AFRL, Wright-Patterson AFB, Ohio
AFRL Materials and Manufacturing Directorate International Award, 2022
AFRL Early Career Award, 2017
Lead Guest Editor for Special Issue in Integrating Materials and Manufacturing Innovation, for the Integrated Computational Materials Engineering of Composites. 2014.
Graduate Excellence in Materials Science (GEMS) Diamond Award, 2009. Awarded by the American Ceramics Society.