Accession Number : AD0853045

Title :   Effect of Notches on Fatigue Strength of Composite Materials.

Descriptive Note : Technical rept.,

Corporate Author : AIR FORCE MATERIALS LAB WRIGHT-PATTERSON AFB OHIO

Personal Author(s) : Boller,Kenneth H.

Report Date : APR 1969

Pagination or Media Count : 60

Abstract : The stress distribution in composite materials is complicated by the joining of elements of different properties. This paper presents a means of estimating the monotonic stress distribution, especially the stress concentration factor, for perforations and edge notches in composite materials; and it presents fatigue data for several geometrical configurations on several composite materials for their fatigue notch sensitivity factor. This study includes (1) theoretical considerations, (2) various sizes of perforations and edge notches, (3) several composite materials providing a range in biaxial elastic constants and anisotropy, (4) photoelastic measurements of peak strains at edge of notch, (5) fatigue testing of at least five replications for median life values of finite width specimens, and (6) fatigue testing by both constant load amplitude and strain amplitude. (Author)

Descriptors :   (*COMPOSITE MATERIALS, FATIGUE(MECHANICS)), GLASS TEXTILES, EPOXY RESINS, TENSILE PROPERTIES, MODULUS OF ELASTICITY, COMPRESSIVE PROPERTIES, POISSONS RATIO, STRESSES, SHEAR STRESSES, STRAIN(MECHANICS), ISOTROPISM, NOTCH SENSITIVITY, PHOTOELASTICITY, LIFE EXPECTANCY

Subject Categories : Ceramics, Refractories and Glass
      Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE