Dr. Brian E. Schuster, associate professor of Metallurgical, Materials and Biomedical Engineering at University of Texas, El Paso will give a seminar titled "Small-scale Quasi-static and Dynamic Fracture of Ceramic Materials" to the interested faculty and students at Discovery Park.

Abstract

Armor ceramic materials including boron carbide and silicon carbide (B4C and SiC) have been in active development domestically for the last eight decades.  Efforts to produce state of the art, high strength, and damage tolerant armor ceramic materials have been hampered by the need to produce bulk specimens for engineering evaluation.  Here, we will review the development and application of two different small-scale experiments that have been used to guide materials-based design efforts for novel ceramic materials.  At the smallest length scales, we used a custom femtosecond laser micromachining apparatus and mechanical testing stage to examine the fracture strengths of microscale tension specimens.  At the millimeter sample scale, we characterized the dynamic fracture and fragmentation behavior of these brittle materials during impact and penetration using time-resolved synchrotron-based X-ray phase contrast imaging during at the Dynamic Compression Sector (DCS, 35-ID-E) at the Advanced Photon Source.  We imaged the incipient fracture behavior in the first microsecond after impact, measured the stresses required for the onset of penetration and estimated the target strengths after the onset of penetration.  The above techniques have been applied widely to a range of different candidate materials including monolithic and ceramic composites, as well as bulk polycrystalline diamond. While some frequently point to optimizing the strength to weight ratio of ceramics (or hardness to density ratio), these results suggest the tensile strength and inelastic response on a 1-D strain loading path are the most important descriptors of a material’s potential in ballistic applications.

Biography

Brian Schuster has served as an Associate Professor of Metallurgical, Materials and Biomedical Engineering at the University of Texas at El Paso ( UTEP) since 2020. He is the Principal Investigator of the Dynamic Materials Laboratory where his research interests include the characterization of the strength and performance of materials at all scales and applied strain rates. He serves as a member of the Dynamic Compression Sector Scientific Working Group at the Advanced Photon Source and as a member of the External Advisory Committee at the Cornell High Energy Synchrotron Source. He previously served as the Team Leader for the Experimental and Computational Group for the US Army Research Laboratory in Aberdeen Proving Ground, MD. He completed his Bachelor of Science in Metallurgical at Materials Engineering at UTEP in 2002 and doctorate in Mechanical Engineering at the Johns Hopkins University in 2008.