Fatigue of unidirectional SCS-6/Ti-24Al-11Nb composite containing a circular hole

Journal Article · Fri Jul 01 04:00:00 EDT 1994 · Metallurgical Transactions, A (Physical Metallurgy and Materials Science); (United States)

DOI:https://doi.org/10.1007/BF02665474· OSTI ID:7028306

Jira, J R; Larsen, J M ^[1]

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1. Wright Lab., Wright-Patterson AFB, OH (United States)

Fatigue tests of notched unidirectional titanium aluminide composite, SCS-6/Ti-24Al-11Nb (at. pct), were performed to characterize the failure modes and mechanisms that control the life of this material. Using middle-hole specimens tested over a range of stress levels, fatigue damage was documented by optical photography, elastic compliance measurements, and electrical potential drop measurements. It was found that a few dominant cracks form near the notch root and propagate into the composite matrix. Chemical removal of the matrix material and metallographic sectioning of fatigue specimens examined prior to failure revealed that extensive fiber bridging of the matrix cracks dominated the fatigue life. A detailed description of the failure modes and mechanisms of damage initiating in the vicinity of a circular hole is presented, and the relative roles of crack initiation and crack growth are discussed.

• OSTI ID: 7028306
• Journal Information: Metallurgical Transactions, A (Physical Metallurgy and Materials Science); (United States), Journal Name: Metallurgical Transactions, A (Physical Metallurgy and Materials Science); (United States) Vol. 25:7; ISSN 0360-2133; ISSN MTTABN
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360603* -- Materials-- Properties
ALLOYS
ALUMINIUM ALLOYS
CARBIDES
CARBON COMPOUNDS
COMPOSITE MATERIALS
CRACK PROPAGATION
DATA
EXPERIMENTAL DATA
FAILURES
FATIGUE
INFORMATION
LIFETIME
MATERIALS
MATERIALS TESTING
MECHANICAL PROPERTIES
MECHANICAL TESTS
NIOBIUM ALLOYS
NUMERICAL DATA
SERVICE LIFE
SILICON CARBIDES
SILICON COMPOUNDS
TESTING
TITANIUM ALLOYS
TITANIUM BASE ALLOYS