A small steel sphere is launched at 153 m/s through a water tank. This is a nice visualization of cavity expansion ion a fluid. Note the rebound as the sphere bounces back and hits the water tank again.
The movie exceeds the 20Mb limit, sio it is available on youtube:
https://www.youtube.com/watch?v=Ihgmp9mlUc8&list=PLTzO8_nj5CcIKB0Qc1ssH…
Shock attenuation is of prime concerns when bodily organs are involved, such as traumatic brain injury. Most armor systems nowadays are aimed at defeating the threat, such as breaking a projectile using hard ceramic armor. Yet, such solutions do not mitigate the initial acceleration (elastic) wave that is responsible for internal organ damage, although no penetration occurred.
The Taylor-Quinney coefficient is universally understood as a manifestation of the stored energy of cold work, and one therefore assumes a one to one correspoindence between its value and the microstructural state of the deformed material. In the attached letter (to appear in Phys Rev Letters), we question this assumption by bringing new experimental evidence that the thermomechanical conversion is a function of the kinetics of the process and not of the final microstructure only.
The Materials Mechanics Center (Technion) mourns the passing away of our respected colleague and founder of the Materials Mechanics Center, Prof. SOL BODNER. May he rest in peace. Our sincere condolences to his family.
The coming ICTAM will be held in Milan, August 23-28, 2020.
Professor K. Kishimoto and myself have been mandated by the Chairs to organize the following thematic session:
SM07 Impact Mechanics and Wave Propagation
We hereby invite our colleagues to submit their abstract and make this session a real success!
Dany and Kikuo
Aqueousmethylcellulose solutions are fascinating inverse-freezing materials, known to reversibly form gels upon heating. Recently, these materials have been found to undergo this endothermic solidification upon impact. The imapct-induced solidification was shown to occur in the microseconds’ timescale, setting the path for examining their functionality for shockabsorption purposes.
All invited to attend a promising conference on defence-related topics, in the broad context of the subject:
Dental implants are increasingly being placed for edentulous patients worldwide. While the clinical aspects of the implants are extensively investigated, engineering considerations of the implant as a functional structure subjected to ill-defined boundary conditions are less considered. A recent trend is to consider all ceramic implants as an alternative to the classical titanium-based implants.
hello:
I attach a flyer for the coming CISM course in Udine.
All welcome
