ENGINEERING ASPECTS OF FRACTURE TOUGHNESS: FIBER REINFORCED LAMINATES

Variables which affect the fracture toughness of several common varieties of fiber reinforced plastics have been investigated experimentally. Fiberglass reinforced plastic composites of the type studied resist crack extension by the growth of subcracks which blunt the main crack tip and reduce the concentration of stress. This mechanism results in an inherently blunt crack tip which may preclude the meaningful application of classical linear elastic fracture mechanics; an alternative fracture criterion based upon a more acceptable generalized stress concentration concept is suggested. The fracture toughness of the composites increases with decreasing temperature and increasing strain rate, but in many cases is insensitive to laminate thickness. While the laminate fracture toughness of the composite is strongly influenced by fiber orientation, fiber volume fraction, and ply stacking arrangement, the properties of the matrix material (epoxy or polyester) have little effect.

• Corporate Authors:

  Massachusetts Institute of Technology

  Sea Grant Program, 77 Massachusetts Avenue
  Cambridge, MA  United States  02139
• Authors:
  • Mandell, J F
  • McGarry, F J
  • Kashihara, R
  • Bishop, W O
• Publication Date: 1973-6

Subject/Index Terms

• TRT Terms: Fracture properties; Glass fiber reinforced plastics; Laminated plastics
• Subject Areas: Marine Transportation; Materials;

Filing Info

• Accession Number: 00057262
• Record Type: Publication
• Source Agency: Massachusetts Institute of Technology
• Report/Paper Numbers: MITSG 73-9
• Files: TRIS
• Created Date: Aug 16 1974 12:00AM