Accession Number:

ADA089894

Title:

Microcracking in Graphite-Epoxy Composites

Descriptive Note:

Interim rept.

Corporate Author:

AEROSPACE CORP EL SEGUNDO CA MATERIALSSCIENCES LAB

Personal Author(s):

• Wolff, Ernest G.

Report Date:

1980-09-01

Pagination or Media Count:

34.0

Abstract:

Microcracking in composite materials is commonly caused by ply stiffness variations in crossply layup during application of applied stress, and by differential thermal expansion coefficients of the fiber and the matrix during thermal excursions. It is responsible for changes in macro- and micromechanical properties, permeability to gases, and dimensional instability. Theories, experimental techniques, and effects of microcracking are reviewed. The coefficient of cracking expansion is defined, and procedures for reducing deleterious effects of microcracking on composite structures are presented.

Descriptors:

• *MECHANICAL PROPERTIES
• *COMPOSITE MATERIALS
• *EPOXY RESINS
• *MICROCRACKING
• STRESSES
• THERMAL PROPERTIES
• STABILITY
• PERMEABILITY
• EXPERIMENTAL DATA
• SIZES(DIMENSIONS)
• STIFFNESS
• TENSILE PROPERTIES
• THEORY
• THERMAL EXPANSION
• ACOUSTIC EMISSIONS
• THERMAL CYCLING TESTS
• REDUCTION(CHEMISTRY)

Subject Categories:

• Laminates and Composite Materials
• Plastics
• Mechanics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE