In-Situ X-Ray Monitoring of Damage Accumulation SiC/RBSN Tensile Specimens
Abstract
The room-temperature tensile testing of silicon carbide fiber- reinforced reaction-bonded silicon nitride (SiC/RBSN) composite specimens was monitored by using in-situ x-ray film radiography. Radiographic evaluation before, during, and after loading provided data on the effect of preexisting volume flaws (high density impurities, and local density variations) on the fracture behavior of composites. Results from composite specimens, showed that x-ray film radiography can monitor damage accumulation during tensile loading. Matrix cracking, fiber-matrix debonding, and fiber pullout were imaged throughout the tensile loading history of the specimens. Further, in-situ film radiography was found to be a helpful and practical technique for estimating interfacial shear strength between the SiC fiber and the RBSN matrix by the matrix crack spacing method. It is concluded that pretest, in-situ, and post- test radiography can provide for a greater understanding of ceramic matrix composite mechanical behavior, a verification of related experimental procedures, and a validation and development of related analytical models.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1991
- Accession Number
- ADA239503
Entities
People
- George Y. Baaklini
- Ramakrishna T. Bhatt
Organizations
- National Aeronautics and Space Administration