Presenter: Prof. Aniruddh Vashisth, University of Washington, Seattle.
The meeting will be hosted by Prof. Tadeusz Uhl.
Seminar topic: “Enhancing Ballistic Impact Resistance of Carbon/Epoxy Tubes Through Variable Nanosilica Content”.
Link to the online seminar (Registration for the online seminar is not required, just join)
Abstract
Laminated fiber-reinforced polymer composites are renowned for their high specific strength and stiffness within the plane of lamination, yet they often suffer from relatively low out-of-plane impact damage tolerance due to matrix-dominated interlaminar mechanical properties.
Various factors, including the toughness of the matrix, can significantly affect the impact response of composites. In this talk, we
will discuss the ballistic impact response of carbon/epoxy tubes with varying nanosilica particle content added to the matrix as a toughening agent.
Measurements were taken for mass density, elastic modulus, glass transition temperature, and Mode I fracture toughness of the matrix materials. Tubes fabricated with these modified matrix materials were subjected to ballistic impacts using a round steel projectile at normal incidence across their major diameter. Post-impact, the tubes underwent nondestructive inspection and mechanical tests to assess residual shear strength in torsion. The results demonstrated that increasing nanosilica concentrations monotonically enhanced the modulus and fracture toughness of the matrix materials. Tubes with nanosilica exhibited smaller impact damage areas, higher residual shear strength, and greater energy absorption per unit damage area compared to control materials without nanosilica.
Overall, the inclusion of nanosilica significantly improved the impact damage resistance and tolerance of carbon/epoxy tubes under torsional loading, with minimal adverse effects on mass density and glass transition temperature.
Bio
Aniruddh’s main areas of interest are in the discovery, development, and deployment of sustainable materials for applications in the mechanical, aerospace, materials, and transportation industries. He did his postdoc in Chemical Engineering from Texas A&M, PhD in Engineering Mechanics from Penn State, and Bachelor’s in Civil Engineering from IIT-BHU, India. His group focuses on understanding the underlying physics of sustainable materials using a closely coupled experimental and theoretical approach. Specifically, his group has two focal areas: (a) sustainability in processing to develop novel, energy-efficient methods for ultrafast synthesis and fabrication of materials and (b) discovering new material chemistries using molecular dynamics and machine learning.
In the future, we hope to converge these two areas of thrust to synthesize new chemistries using novel synthesis methodologies. Aniruddh’s molecular dynamics frameworks have been implemented in multiple software including Software for Chemistry of Materials ADF and LAMMPS. Additionally, Aniruddh holds 4 patents (granted and pending) on the application of RF heating for material processing. His work is funded by companies and federal agencies such as The Boeing Company, Department of Energy, Microsoft, Lynntech, Navy, and Army.
