A STUDY ON FRACTURE TOUGHNESS OF ADVANCED STRUCTURAL COMPOSITES

The basic concept of structural fracture in homogeneous, isotropic materials is discussed. Fundamental relationships associated with the linear elastic fracture mechanics, based on the Griffith-Irwin approach, are presented. Discussed next are properties of fiber reinforced (or filamentary) composite materials from fracture mechanics point of view. Representative fracture test results are then reviewed and analyzed. Involved in the tests are numerous composites such as beryllium/aluminum, glass/epoxy, Scotchply, boron/aluminum, graphite/polyimide, etc. Some of these nonhomogeneous anisotropic composites are unidirectionally reinforced, while other are angle-plied. Finally, the fracture phenomenon and process in filamentary composites are discussed in details. It is found that the linear elastic fracture mechanics is applicable to most composite materials which have been investigated. It is nevertheless premature and risky to predict the applicability of the theory to the filamentary composite materials in general. The report includes recommendations for future work on fracture of structural composites intended for high-performance flight vehicles.

• Corporate Authors:

  Naval Air Development Center

  Air Vehicle Technology Department
  Warminster, PA  United States 
• Authors:
  • Chang, G C
• Publication Date: 1973-7

Media Info

• Features: References;
• Pagination: 106 p.

Subject/Index Terms

• TRT Terms: Composite materials; Cracking; Fracture mechanics; Fracture properties; Stresses
• Uncontrolled Terms: Stress intensity factors
• Old TRIS Terms: Crack formation
• Subject Areas: Marine Transportation; Materials;

Filing Info

• Accession Number: 00047679
• Record Type: Publication
• Source Agency: Ship Structure Committee
• Report/Paper Numbers: EW-4-73
• Files: TRIS
• Created Date: Oct 31 1974 12:00AM