Response of Non-Woven Synthetic Fiber Textiles to Ballistic Impact.
Abstract
When organic fiber felt materials are impacted by blunt fragments, stress waves propagating laterally into the material transfer projectile momentum to an increasing (roughly conical) volume of felt material. By applying a retarding force to the projectile, stresses in the felts can be maintained below rupture values, provided that the felts are free to move in the direction of the projectile. The objective of this program was to define the transient behavior of the felt and the force interaction between it and the projectile. CAn experimental technique was developed whereby the position-time histories of eleven points (spark gaps) on the rear surface of a felt sample could be determined. The center spark station, being on the projectile trajectory, provides projectile displacement-time data. Other stations provide both radial and transverse displacements. The longitudinal radial wave gives material particles an initial radial velocity inward; later, the slower moving transverse wave imparts a transverse velocity to the felt, usually stopping or reversing radial motion. Measurement errors average less than two percent. felt samples (nylon (3), orlon, dacron, polypropylene) were tested using the 17-grain fragment simulating projectile at various velocities up to and greater than the ballistic limit velocity. Graphical differentiation was used to obtain velocity-time, force-time, and force - distance relationships. Qualitative evaluations reveal that strength, elongation, and transverse wave velocity are the three pre-dominant parameters in determining effectiveness. The energy absorbed by a felt is maximum at the ballistic limit velocity and decreases dramatically at higher (complete perforation) velocities. An analytical model based upon momentum considerations is compared to the experimental results.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 1966
- Accession Number
- ADA307836
Entities
People
- Edward P. Wittrock
- Thomas W. Ipson
Organizations
- Denver Research Institute