Engineering Energetic Materials (Steve Beaudoin, Purdue)

Abstract:

Energetic materials (propellants, explosives, and pyrotechnics) are defined by their unusually high energy density and their ability to release this energy rapidly. They find uses in civilian and military applications. The Purdue Energetics Research Center (PERC) is the largest academic center in the US focusing on energetic materials. PERC supports laboratory and computational research spanning the complete range of activities from the design and synthesis of new energetic molecules to the development of new manufacturing paradigms for their production. One area of great interest in PERC is the additive manufacturing of energetic materials. In this work, adhesion in additively manufactured energetic composites is evaluated at both the particle and composite scales.  First, the fracture toughness of the welds between additively manufactured lines is investigated using Y-shaped cutting to obtain materially intrinsic values of G, the strain energy release rate due to fracture. These results were obtained using the Soft-Matter, Low-Friction, Y-Shaped Cutting Experimental Rig (SLYCER), a specialized testing rig created to evaluate fracture behavior. Next, a modified centrifuge method is applied to assess energetic particle adhesion to surfaces. This uses a van der Waals-steric force model that accounts for both surface roughness and the particle size distribution to describe the observed removal curves. We also make use of the Wasserstein metric to determine the Hamaker constant that best describes a given system. Preliminary results show that this new method can accurately describe experimentally observed results with Hamaker constant values whose magnitudes are in agreement with the Lifshitz theory.

Biography:

Stephen P. (Steve) Beaudoin is a professor in the Davidson School of Chemical Engineering at Purdue University, where he serves as the Founding Director of the Purdue Energetics Research Center (PERC; https://engineering.purdue.edu/Energetics). Under his guidance, PERC has grown to have more than 200 ITAR-eligible student, faculty, and staff participants, and is the largest academic research center of its kind in the U.S. Beaudoin is known for his work on powder and particle adhesion. He has published more than 100 manuscripts in the refereed literature and made more than 200 technical presentations in this area. His current focus is adhesion, mixing/formulation, manufacturing, and additive manufacturing,all targeting energetic materials. Beaudoin has developed multiple educational programs on defense related topics to serve various DoD partners. Beaudoin earned a B.S. in Chemical Engineering from MIT in 1988, an M.S. in Chemical Engineering from the University of Texas at Austin in 1990, and a Ph.D. in Chemical Engineering from North Carolina State University in 1995.