Thermomechanical processing, phase transformations and mechanical properties of Ti-25Al-10Nb-3V-1Mo

Conference · Sun Dec 31 04:00:00 EST 1995

OSTI ID:186737

Kumpfert, J; Peters, M; Kaysser, W A ^[1]; Ward, C H ^[2]

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1. DLR, Cologne (Germany). Inst. of Materials Research
2. AFOSR/NA, Bolling AFB, DC (United States)

Increasing niobium content is known to increase strength, toughness and ductility of Ti{sub 3}Al-based alloys by stabilizing the orthorhombic phase (Ti{sub 2}AlNb), at the expense, however, of density. It will be shown, that the alloy Ti-25Al-1-Nb-3V-1Mo, having a relatively low content of {beta}-stabilizing elements, can be processed in a way to produce a high volume fraction of the orthorhombic phase with a fine microstructure. As a result, extremely high yield strength values close to 1,400 MPa at reasonable room temperature ductility of about 3% can be observed. To produce such microstructures, phase transformations needed to be known in Ti-25Al-10Nb-3V-1Mo and were investigated by TEM and XRD. A new TTT-diagram will be proposed and related to the observed microstructures and mechanical properties. Depending on the microstructure, an extreme variation of the tensile strength and deformation behavior can be obtained.

• OSTI ID: 186737
• Report Number(s): CONF-950201--; ISBN 0-87339-316-3
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
AGING
ALUMINIUM ALLOYS
DUCTILITY
HARDNESS
INTERMETALLIC COMPOUNDS
LAMELLAE
MICROSTRUCTURE
MOLYBDENUM ALLOYS
NIOBIUM ALLOYS
OPTICAL MICROSCOPY
ORTHORHOMBIC LATTICES
PHASE TRANSFORMATIONS
PRECIPITATION
TENSILE PROPERTIES
THERMOMECHANICAL TREATMENTS
TITANIUM ALLOYS
TRANSMISSION ELECTRON MICROSCOPY
VANADIUM ALLOYS
X-RAY DIFFRACTION
YIELD STRENGTH