Accession Number : ADA325704

Title :   On the Application of Dynamic Fracture Mechanics to Continuous Fiber Reinforced Composite Materials.

Descriptive Note : Annual rept. 1 Jun 96-31 May 97,

Corporate Author : NOTRE DAME UNIV IN DEPT OF AEROSPACE AND MECHANICAL ENGINEERING

Personal Author(s) : Mason, J. J.

PDF Url : ADA325704

Report Date : MAY 1997

Pagination or Media Count : 30

Abstract : Progress is reviewed with emphasis on a model of stress intensity factors in dynamic punch test. The specimen is assumed to be initially at rest and the projectile is rigid. Impact of the rigid projectile is modeled by a constant velocity condition on the impact surface. Three support geometries are considered for each specimen geometry: a free back surface, a fixed back surface, and a two dimensional punch. Analytical approximations for the stress intensity factor history are given for short times, while dynamic quarter point finite element solutions are included for longer times. The stress intensity factor is shown to increase with time due to wave reflection in the two dimensional punch and fixed back support geometries, while it decreases with time for the free back surface. The stress intensity factors in the plate specimen are also greater than those in the edge notched specimen in all tests. For applicability to manufacturing operations and increased chance of shear dominated failure, it is recommended that the two dimensional punch or fixed back surface geometries of the plate specimen be used in experimental studies.

Descriptors :   *DYNAMICS, *FIBER REINFORCED COMPOSITES, *FRACTURE(MECHANICS), VELOCITY, EXPERIMENTAL DATA, MANUFACTURING, IMPACT, COMPOSITE MATERIALS, FINITE ELEMENT ANALYSIS, INTENSITY, SURFACES, APPROXIMATION(MATHEMATICS), RIGIDITY, WAVES, STRESS CONCENTRATION.

Subject Categories : Laminates and Composite Materials
      Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE