Effect of particle morphology on input and propagated stress wave profiles for two highly-porous polytetrafluoroethylene powders
- Naval Surface Warfare Center, Dahlgren, VA (United States). Dahlgren Div.
- Sandia National Labs., Albuquerque, NM (United States)
Piezoelectric polymer stress gauges in copper fixtures were used with te Sandia 2.5-inch bore gas gun to obtain time-resolved pressure measurements for two polytetrafluoroethylene powders having significantly different particle morphologies. The powders had approximate average particle sizes of 534 microns and 28 microns, respectively, and scanning electron microscopy revealed differences in the appearances of representative particle surfaces. The range of input stresses was from 0.13 GPa to 2.81 GPa, and the initial densities were 57% of the solid density. The ``crush strength`` (pressure required to compress the porous compact to solid density) was close to 1.0 GPa for the coarse material as compared to 0.6 GPa for the finer material. At an input stress of about 0.6 GPa, the risetime of the propagated stress waves in the coarse material was approximately 240 nsec compared to 50 nsec for the finer material. These measurements show the strongly rate-dependent deformation of the powders and that particle morphology has a significant effect on the shock compression.
- Research Organization:
- Sandia National Labs., Albuquerque, NM (United States)
- Sponsoring Organization:
- USDOE, Washington, DC (United States); Department of Defense, Washington, DC (United States)
- DOE Contract Number:
- AC04-94AL85000
- OSTI ID:
- 103132
- Report Number(s):
- SAND--95-2057C; CONF-950846--41; ON: DE95017839
- Country of Publication:
- United States
- Language:
- English
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