Accession Number : ADA313646

Title :   Dynamic Inelasticity of Polymer-Matrix Composites.

Descriptive Note : Final rept. Apr-Oct 95,

Corporate Author : PURDUE UNIV LAFAYETTE IN

Personal Author(s) : Espinosa, Horacio D.

PDF Url : ADA313646

Report Date : 16 MAY 1996

Pagination or Media Count : 37

Abstract : A novel experimental configuration that can record projectile velocity histories and target back surface out-of-plane motion in penetration experiments has been developed. The technique was used to investigate failure mechanisms during ballistic impact of an S-2 glass fiber woven composite with 60% fiber volume fraction. Microscopy studies performed on recovered samples clearly show interply delamination, fiber breakage, ply inelasticity, and fiber kinking as the major failure modes in these composites. Recorded penetrator velocity histories indicate these failure mechanisms are rate dependent. Pressure-shear recovery experiments were performed to investigate the out-of-plane dynamic shear resistance of the composite. Microstructural analyses revealed that at low impact velocities, 2 GPa compressive stresses, matrix cracking and matrix-fiber debonding are the primary damage mechanisms. At higher impact velocities, 4 GPa compressive stresses, fiber microcracking becomes pronounced.

Descriptors :   *DYNAMICS, *POLYMERS, *COMPOSITE MATERIALS, *ELASTIC PROPERTIES, *MATRIX MATERIALS, *GLASS FIBERS, SHEAR PROPERTIES, STRESSES, VELOCITY, MICROSTRUCTURE, IMPACT, DAMAGE, PROJECTILES, RESISTANCE, STRUCTURAL ANALYSIS, CRACKING(FRACTURING), FAILURE, MICROSCOPY, LOW VELOCITY, PENETRATION, BALLISTICS, COMPRESSIVE PROPERTIES, MICROCRACKING.

Subject Categories : Polymer Chemistry
      Ceramics, Refractories and Glass
      Laminates and Composite Materials
      Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE