Team Members & Roles:
Joshua Gelfond: Team Lead
George Olisedeme-Akpu: Analysis Lead
Thebeau Paul: Evaluation Lead
James White: Design/Fabrication Lead
Abstract: The development of new alloys creates the need for microscopic ballistic testing under extreme conditions. Using the laser-induced projectile impact test (LIPIT), ultrahigh strain rates up to 108/s can be achieved. To better understand the material properties of these new alloys, many of these tests are performed at frigid conditions with temperatures as low as -190°C. In order to perform these experiments, a cryogenic sample mount is required to cool these material samples to the desired temperature using liquid nitrogen (LN2) while being contained within a vacuum chamber to reduce frost build-up. Our team developed an assembly consisting of a copper stage and aluminum mounting arm capable of cooling the sample from room temperature down to the LN2 temperature of -188°C in 6 minutes and 44 seconds. The components were fastened using thermally resistant materials to isolate the cooling stage and mitigate conductive heat loss. By minimizing the mass of the copper stage we were able to reach a maximum cooling rate of -2.4°C/sec.
This material is based upon work supported by the Department of Energy – National Nuclear Security Administration under Award Number DE-NA0004154.