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Meeting ID: 976 4289 1575
Passcode: 106651

High-fidelity mechanical characterization of materials at high strain rates is needed to evaluate material performance prior to shock and impact applications. Since developed by Kolsky in 1949, Kolsky bars have been recognized as an effective and efficient tool to evaluate mechanical performance of materials in extreme environments from low-speed crash to high speed impact, penetration, or even explosion. Although first developed for dynamic compression tests, the Kolsky bar technique has been modified and extended for characterizing material response in different mechanical environments for different applications.    

In this lecture, an overview and most recent advances of the Kolsky bar technique for dynamic characterization of materials, from soft polymers to hard ceramics, are presented with focuses on stress-strain response, fracture and failure, as well as energy dissipation at different loading modes (compression, tension, and shear), stress states (unconfined and confined), and temperatures (from cold to hot). Experimental challenges and data interpretation in such dynamic characterization tests are detailed. The dynamic material property information provides not only insights for rate-dependent material model development, calibration, and validation but also recommendation of material utilization, selection, and potential optimization particularly for shock and impact applications. The path forward for mechanical characterization of advanced materials is also briefed.