Impact Damage in Curved Graphite/Epoxy Panels with Clamped Edges

Abstract

Graphite/epoxy curved cylindrical panels were impacted in the center by an impact machine capable of measuring load during the test. Load, deflection and strain as functions of time were measured for six symmetric layup configurations for impact energies of 0.5 to 4.5 ft-lb. Damage was produced in all panels for certain impact energies. The extent and location of damage was determined from C-scans and optical microscopy of panel cross-sections. The cross-sections indicated that both delamination and transverse cracking contribute to internal damage. An in-house nonlinear finite element code was used to predict the panel deflections and stresses. The analysis produced good results in predicting the panel deflection and indicated transverse failure stresses were present in the panel center region. The deflections indicated that the panel was in between simply supported and clamped boundary conditions, with good agreement obtained for hinged support at each edge.

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Document Details

Document Type
Technical Report
Publication Date
Dec 01, 1990
Accession Number
ADA230853

Entities

People

  • Ronald B. Perry

Organizations

  • Air Force Institute of Technology

Tags

DTIC Thesaurus Topics

  • Composite Materials
  • Data Acquisition
  • Detectors
  • Experimental Data
  • Fibers
  • Geometry
  • Graphitic Materials
  • Laminates
  • Load Cells
  • Materials
  • Materials Testing
  • Measurement
  • Mechanics
  • Optical Detectors
  • Plastic Explosives
  • Strain Gages
  • Stress Strain Relations

Fields of Study

  • Physics

Readers

  • Structural Dynamics.
  • Structural Health Monitoring of Composite Structures.