Rate and environmental effects on fracture of a two-phase TiAl-alloy. [Ti-47Al-2. 6Nb-0. 93Cr-0. 85V]
- Southwest Research Inst., San Antonio, TX (United States)
- Universal Energy Systems, Dayton, OH (United States)
The influence of strain rate and environment on the fracture behavior of a two-phase TiAl-alloy, Ti-47Al-2.6Nb-2(Cr + V), heat-treated to a nearly fully lamellar microstructure has been studied by performing conventional tensile, compression, and fracture toughness tests in air, argon, and vacuum at 25 C and 800 C. Both tensile and compression tests were conducted at strain rates of 1 x 10[sup [minus]3] and 1 x 10[sup [minus]5] s[sup [minus]1] , and fracture toughness tests were performed under displacement rates of 0.25 to 2.5 mm/min. In addition, in situ fracture toughness tests were conducted at slow rates both in vacuum and in air. The results indicated that both strain rate and environment affected the tensile stress-strain behavior and ductility and the fracture resistance of the TiAl-alloy at 800 C. In contrast, neither the tensile ductility nor the fracture toughness was significantly affected by the environment at ambient temperature. For compression in air, the stress-strain behavior was insensitive to both strain rate and test temperature within the conditions tested. Studies of fracture surfaces revealed that low tensile ductility in this alloy at ambient temperature is associated with the tendency to delaminate along [gamma]/[gamma] and [gamma]/[alpha][sub 2] interfaces.
- OSTI ID:
- 6310874
- 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. 24:1; ISSN 0360-2133; ISSN MTTABN
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
360103* -- Metals & Alloys-- Mechanical Properties
ALLOYS
ALUMINIUM ALLOYS
CHROMIUM ADDITIONS
CHROMIUM ALLOYS
COMPRESSION STRENGTH
DATA
DEFORMATION
DUCTILITY
EXPERIMENTAL DATA
FRACTURE PROPERTIES
HEAT TREATMENTS
INFORMATION
INTERMETALLIC COMPOUNDS
LAMELLAE
LAYERS
MATERIALS TESTING
MECHANICAL PROPERTIES
MECHANICAL TESTS
MICROSTRUCTURE
NIOBIUM ALLOYS
NUMERICAL DATA
STRAIN RATE
TEMPERATURE DEPENDENCE
TENSILE PROPERTIES
TESTING
TITANIUM ALLOYS
TITANIUM BASE ALLOYS
VANADIUM ADDITIONS
VANADIUM ALLOYS