Damping Loss Factor Determination of Glass and Graphite Epoxy Laminated Composites Using Vertically Oriented Cantilever Beams

Abstract

Material damping of laminated composites is experimentally determined using a cantilever beam test with an impulse excitation. The beam is oriented vertically as opposed to the traditional horizontal orientation. Data acquisition and manipulation is carried out using an IBM PC-AT with a high speed, A/D board and analysis software. Unidirectional continuous fiber 0, 90 and + or - 45 degree laminates were fabricated from glass/epoxy (Hercules S2- Glass/3501-6) and graphite/epoxy (Hercules AS4/3501-6) to investigate the effect of fiber and matrix properties as a function of frequency, up to 1000 Hz., on the damping of composites. The vertical orientation provided loss factor results that were significantly different than the tests conducted on the horizontally oriented beams. The results using the vertical orientation are assumed to be more representative of the material loss factor since both accelerations and stresses are more uniform. The glass fiber composite had a higher loss factor than the graphite composites. The loss factor for the 0 degree AS4/3501-6 increased linearly as a function of frequency, whereas the 0 degree S2-Glass/ 3501-6 had a significant nonlinear increase in loss factor above 700 Hz. (aw)

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Document Details

Document Type
Technical Report
Publication Date
Nov 01, 1989
Accession Number
ADA216529

Entities

People

  • Roger M. Crane

Tags

Communities of Interest

  • Energy and Power Technologies
  • Ground and Sea Platforms

DTIC Thesaurus Topics

  • Composite Material Fabrication
  • Composite Materials
  • Data Acquisition
  • Eddy Currents
  • Epoxy Composites
  • Fabrication
  • Fibers
  • Frequency
  • Graphitic Materials
  • Laminates
  • Materials
  • Materials Laboratories
  • Materials Processing
  • Materials Science
  • Mechanical Properties
  • Orientation (Direction)
  • Vertical Orientation

Fields of Study

  • Materials science

Readers

  • Control Systems Engineering.
  • Electromagnetic Wave Scattering and Antenna Radiation Engineering
  • Reinforced Composite Materials