by
Assistant Professor | Mechanical Engineering
University of Utah
Friday, November 22
2 - 3 PM
MK 317
About the Talk:
In recent years, high-resolution X-ray micro-computed tomography (mCT) has emerged as a preferred method for imaging microstructure and damage in a variety of natural and engineered materials. For advanced aerospace composites, X-ray mCT has been successfully used to study 3D formation and evolution of delamination and transverse fracture, fiber tensile and compressive failure, fatigue-induced damage, and damage resulting from extreme thermomechanical environments. In addition, X-ray mCT has been used for imaging the internal microstructure of composites, including location, shape, and size of reinforcing fibers, voids, and manufacturing-induced flaws. As such, the 3D image data derived from X-ray mCT has challenged the way in which we perceive the interplay between the underlying microstructure of composites and their long term damage resistance and tolerance.
In this talk, I will begin by giving a short overview of X-ray mCT, including a brief discussion on the advantages and disadvantages of existing lab- and synchrotron-based X-ray mCT systems. I will then discuss two examples of using X-ray mCT to study composite systems that are of interest to the aerospace community. In the first example, I will discuss our attempt to image the entire life cycle of SiC/SiC ceramic-matrix composites, focusing primarily on the evolution of porosity and shrinkage cracks during multi-step polymer infiltration and pyrolysis. Next, I will describe a new in situ imaging experiment, conducted at the Advanced Light Source beamline 8.3.2, to image initiation and evolution of transverse cracks in polymer matrix composites subjected to flexure. I will conclude my talk by describing my group’s efforts to develop a new synchrotron-based nano-tomography beamline at the Advanced Light Source and the associated challenges with collecting, processing, and analyzing large quantities (i.e. TBs) of X-ray mCT image data.
About the Speaker:
Dr. Michael Czabaj is an assistant professor in the Department of Mechanical Engineering at the University of Utah and is a director of the Utah Composites Laboratory. Dr. Czabaj’s research interests are in the broad area of experimental and computational mechanics of composites, with specific focus on fracture mechanics, micromechanics, and nondestructive imaging using X-ray computed tomography. Prior to his position at the University of Utah, Dr. Czabaj was a Materials Engineer at NASA Langley Research Center. Dr. Czabaj received his doctorate in Theoretical and Applied Mechanics from Cornell University and bachelor’s degree in Aerospace Engineering from Syracuse University.