Modeling fatigue crack growth in cross ply titanium matrix composites
In this study, the fatigue crack growth behavior of fiber bridging matrix cracks in cross-ply SCS-6/Ti-15-3 and SCS-6/Timetal-21S laminates containing center holes was investigated. Experimental observations revealed that matrix cracking was far more extensive and wide spread in the SCS-6/Ti-15-3 laminates compared to that in the SCS-6/Timetal-21S laminates. In addition, the fatigue life of the SCS-6/Ti-15-3 laminates was significantly longer than that of the SCS-6/Timetal-21S laminates. The matrix cracking observed in both material systems was analyzed using a fiber bridging (FB) model which was formulated using the boundary correction factors and weight functions for center hole specimen configurations. A frictional shear stress is assumed in the FB model and was used as a curve fitting parameter to model matrix crack growth data. The higher frictional shear stresses calculated in the SCS-6/Timetal-21S laminates resulted in lower stress intensity factors in the matrix and higher axial stresses in the fibers compared to those in the SCS-6/Ti-15-3 laminates at the same applied stress levels.
- Research Organization:
- National Aeronautics and Space Administration, Hampton, VA (United States). Langley Research Center
- OSTI ID:
- 6219350
- Report Number(s):
- N-93-27062; NASA-TM-108988; NAS-1.15:108988; CONF-930532-; CNN: RTOP 763-23-45-85
- Resource Relation:
- Conference: 5. ASTM symposium on composite materials: fatigue and fracture, Atlanta, GA (United States), 4-6 May 1993
- Country of Publication:
- United States
- Language:
- English
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