Accession Number:

AD0780106

Title:

Fatigue Crack Initiation in a Boron Epoxy Plate with a Circular Hole.

Descriptive Note:

Interim rept.,

Corporate Author:

VIRGINIA POLYTECHNIC INST AND STATE UNIV BLACKSBURG DEPT OF ENGINEERING SCIENCE AND MECHANICS

Personal Author(s):

• Marcus,Larry A.
• Stinchcomb,Wayne W.
• Turgay,Haldun M.

Report Date:

1974-02-01

Pagination or Media Count:

68.0

Abstract:

Numerical results for the stress state around a circular hole in a 0plus or minus 450s boron-epoxy plate under tensile loading are presented. This serves as a model for the initial stress state around the hole during fatigue loading. Comparison is drawn with experimental results for a fatigued specimen obtained from thermography and radiography. Using these results an interpretation of the effects of the initial stress state on the thermal behavior and on failure initiation is given. This interpretation shows that the circumferential normal stresses are responsible for heat generation, and failure initiation is influenced by the interlaminar shear stresses in the outer 0 and 45 degree layers. Author-PL

Descriptors:

• *Laminates
• *Fiber reinforced composites
• *Fatigue(Mechanics)
• Crack propagation
• Plates
• Shear stresses
• Thermography
• Radiography
• Strain(Mechanics)

Subject Categories:

• Laminates and Composite Materials

Distribution Statement:

APPROVED FOR PUBLIC RELEASE