Damage development in titanium metal matrix composites subjected to cyclic loading

Conference · Wed Apr 01 04:00:00 EST 1992

OSTI ID:7070721

Johnson, W S

Several layups of SCS-6/Ti-15-3 composites were investigated. Fatigue tests were conducted and analyzed for both notched and unnotched specimens at room temperature and elevated temperatures. Thermo-mechanical fatigue results were analyzed. Test results indicated that the stress in the 0 degree fibers is the controlling factor in fatigue life. The static and fatigue strength of these materials is shown to be strongly dependent on the level of residual stresses and the fiber/matrix interfacial strength. Fatigue tests of notched specimens showed that cracks can initiate and grow many fiber spacings in the matrix materials without breaking fibers. Fiber bridging models were applied to characterize the crack growth behavior. The matrix cracks are shown to significantly reduce the residual strength of notched composites. The notch strength of these composites was accurately predicted using a micromechanics based methodology.

• Research Organization: National Aeronautics and Space Administration, Hampton, VA (United States). Langley Research Center
• OSTI ID: 7070721
• Report Number(s): N-92-23433; NASA-TM--107597; NAS--1.15:107597; CONF-920339--
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360603* -- Materials-- Properties
ALLOYS
AMBIENT TEMPERATURE
CARBIDES
CARBON COMPOUNDS
COMPOSITE MATERIALS
CRACK PROPAGATION
CRACKS
DAMAGE
FATIGUE
FRACTURE PROPERTIES
MATERIALS
MATRIX MATERIALS
MECHANICAL PROPERTIES
RESIDUAL STRESSES
SILICON CARBIDES
SILICON COMPOUNDS
STRESSES
THERMODYNAMICS
TITANIUM ALLOYS
TITANIUM BASE ALLOYS