Dynamic environmental embrittlement of an [alpha][sub 2] titanium aluminide. [Ti-25Al-10Nb-3V-1Mo]
- Wright Lab., Wright-Patterson, OH (United States)
- Engineering Materials Technology Lab., Cincinnati, OH (United States)
- Carnegie Mellon Univ., Pittsburgh, PA (United States)
Titanium aluminide alloys based on the [alpha][sub 2] phase were originally developed to extend the application range of titanium by providing improved elevated temperature strength and environmental resistance. These improvements were to come from the much larger concentrations of aluminum added to make these alloys. It was hoped that the increased amount of aluminum would favor the formation of a continuous, environmentally protective layer of alumina, Al[sub 2]O[sub 3], at the alloy's surface. Tensile and creep testing these alloys at elevated temperatures ([ge][approximately]450 C) in an air environment results in circumferential cracking along the specimen surface. This cracking can lead to premature failure as compared to vacuum testing. Balsone has observed this behavior in Ti-24Al-11Nb tensile tested in air. He repeated the tensile testing in vacuum at 550 C and 650 C, finding that the surface cracking disappeared and that the tensile elongation was significantly increased. From this, Balsone deduced that there was a significant effect of the environment, presumably oxygen embrittlement, on tensile properties at temperatures as low as 550 C. Vacuum tensile testing of Ti-25Al-10Nb-3V-1Mo (Ti-25-10-3-1) also results in a significant improvement in tensile elongation. The intent of the present investigation was to further study the effect of an air environment at elevated temperature on the tensile elongation of Ti-25-10-3-1. In particular, environmentally assisted surface crack growth into the tensile specimen was of interest.
- OSTI ID:
- 6613827
- Journal Information:
- Scripta Metallurgica et Materialia; (United States), Vol. 28:9; ISSN 0956-716X
- Country of Publication:
- United States
- Language:
- English
Similar Records
Elevated temperature tensile behavior of Ti-25Al-10Nb-3V-1Mo
Microstructural effects on the deformation and fracture of the alloy Ti-25Al-10Nb-3B-1Mo. Final report, 1 July 1988-15 December 1992
Related Subjects
ALUMINIUM ALLOYS
EMBRITTLEMENT
MOLYBDENUM ALLOYS
NIOBIUM ALLOYS
TITANIUM BASE ALLOYS
VANADIUM ALLOYS
AIR
ALLOY SYSTEMS
CRACK PROPAGATION
CREEP
ELONGATION
ENVIRONMENT
EXPERIMENTAL DATA
TENSILE PROPERTIES
ALLOYS
DATA
FLUIDS
GASES
INFORMATION
MECHANICAL PROPERTIES
NUMERICAL DATA
TITANIUM ALLOYS
360103* - Metals & Alloys- Mechanical Properties