The research objective of this award is to identify and mitigate the mechanisms responsible for bond degradation in the Ultrasonic Consolidation manufacturing process. To achieve this objective, a multi-level research framework that combines theories of non-smooth systems dynamics with computational algorithms and a specially-developed experimental module will be used. At the first level, Hamilton's principle is combined with a Rayleigh-Ritz approach to develop a reduced-order model, which describes the build feature's response to ultrasonic excitations. At the second level, mathematical models are derived to describe the stick-slip response of the feature due to frictional interactions. The derived models are then experimentally validated and combined to understand how changes in the build feature's geometry and material properties influence stresses and subsequent interface bonding. The knowledge is used to devise strategies to mitigate bond degradation.
If successful, this endeavor will provide the necessary tools to overcome a hurdle that is preventing the broad use of the promising Ultrasonic Consolidation manufacturing process. By providing a mechanism to bond dissimilar materials, and embed electronics and fiber reinforcements in metallic structures, Ultrasonic Consolidation permits manufacturing machine components and structural systems with unique performance capabilities. This includes functionally-graded structures, metal-matrix composites, fiber embedded adaptive systems, and self-sensing components that are essential for the health-monitoring of machines and structures. Research results will also be widely published to enable students and engineers to see the critical link between dynamics and manufacturing. An educational outreach initiative that integrates research with education through exciting activities is also planned to promote diversity through recruitment of minority students.
