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Title: Perforation of woven fabric by spherical projectiles

Abstract

Rectangular specimens of Twaron{reg_sign} fabric, clamped on two opposite sides, are subjected to impact perforation by 9.5 mm diameter spherical steel projectiles at speeds ranging from 140 m/s to 420 m/s. This plain woven fabric, comprising PPTA (poly-paraphenylene terepthalamide) fibers, is commonly employed in flexible an-nor applications. Its perforation response is examined in terms of residual velocity, energy absorbed and resulting deformation patterns. The existence of a critical or transition impact velocity, beyond which there is a significant reduction in energy absorbed by perforation, is observed. Differences in creasing and deformation induced in specimens are also demarcated by this transition impact velocity. Effects of difference in boundary conditions (clamped and free) on yarn breakage are also noted. A numerical model, based on an initially orthogonal network of pin-jointed bars interconnected at nodes, is formulated to simulate the fabric. Fiber yam mechanical properties are represented via a three-element spring-dashpot model which encapsulates viscoelastic behavior and fiber failure. Numerical results exhibit good correlation with experimental observations in terms of prediction of threshold perforation velocity, energy absorbed, occurrence of a transition critical velocity and fabric deformation characteristics.

Authors:
; ;  [1]
  1. National Univ. of Singapore (Singapore)
Publication Date:
OSTI Identifier:
175416
Report Number(s):
CONF-950686-
TRN: 95:006111-0391
Resource Type:
Conference
Resource Relation:
Conference: Joint applied mechanics and materials summer meeting, Los Angeles, CA (United States), 28-30 Jun 1995; Other Information: PBD: 1995; Related Information: Is Part Of AMD - MD `95: Summer conference; PB: 520 p.
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; 45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEFENSE; ARMOR; PERFORATION; POLYMERS; BOUNDARY CONDITIONS; CRITICAL VELOCITY; DEFORMATION; MECHANICAL PROPERTIES; FIBERS; PROJECTILES; MILITARY EQUIPMENT; IMPACT TESTS

Citation Formats

Shim, V.P.W., Tan, V.B.C., and Tay, T.E. Perforation of woven fabric by spherical projectiles. United States: N. p., 1995. Web.
Shim, V.P.W., Tan, V.B.C., & Tay, T.E. Perforation of woven fabric by spherical projectiles. United States.
Shim, V.P.W., Tan, V.B.C., and Tay, T.E. Sun . "Perforation of woven fabric by spherical projectiles". United States. doi:.
@article{osti_175416,
title = {Perforation of woven fabric by spherical projectiles},
author = {Shim, V.P.W. and Tan, V.B.C. and Tay, T.E.},
abstractNote = {Rectangular specimens of Twaron{reg_sign} fabric, clamped on two opposite sides, are subjected to impact perforation by 9.5 mm diameter spherical steel projectiles at speeds ranging from 140 m/s to 420 m/s. This plain woven fabric, comprising PPTA (poly-paraphenylene terepthalamide) fibers, is commonly employed in flexible an-nor applications. Its perforation response is examined in terms of residual velocity, energy absorbed and resulting deformation patterns. The existence of a critical or transition impact velocity, beyond which there is a significant reduction in energy absorbed by perforation, is observed. Differences in creasing and deformation induced in specimens are also demarcated by this transition impact velocity. Effects of difference in boundary conditions (clamped and free) on yarn breakage are also noted. A numerical model, based on an initially orthogonal network of pin-jointed bars interconnected at nodes, is formulated to simulate the fabric. Fiber yam mechanical properties are represented via a three-element spring-dashpot model which encapsulates viscoelastic behavior and fiber failure. Numerical results exhibit good correlation with experimental observations in terms of prediction of threshold perforation velocity, energy absorbed, occurrence of a transition critical velocity and fabric deformation characteristics.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Sun Dec 31 00:00:00 EST 1995},
month = {Sun Dec 31 00:00:00 EST 1995}
}

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