Bulk deformation of Ti-6.8Mo-4.5Fe-1.5Al (Timetal LCB) alloy

Journal Article · Sat Jun 01 04:00:00 EDT 1996 · Journal of Materials Engineering and Performance

DOI:https://doi.org/10.1007/BF02649336· OSTI ID:271746

Weiss, I; Srinivasan, R; Saqib, M; Stefansson, N ^[1]; Jackson, A G; LeClair, S R ^[2]

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1. Wright State Univ., Dayton, OH (United States). Mechanical and Materials Engineering Dept.
2. Wright Lab.-Materials Directorate, Wright-Patterson AFB, OH (United States)

Recently, a low-cost near-{beta} titanium alloy (Timetal LCB Ti-6.8Mo-4.5Fe-1.5Al wt%) containing iron and molybdenum has been developed. This alloy is cold formable in the {beta} microstructure and can be aged to high strengths by precipitating the {alpha} phase. Due to its combination of cold formability and high strength, the alloy is a potential replacement for steel components in the automotive industry. The current study was undertaken to evaluate the cold bulk forming characteristics of Timetal LCB for use in lightweight automotive applications. Room-temperature compression tests conducted over a strain-rate range of 0.01 to 5/s indicate that the bulk cold compression of the alloy is affected by two factors: the microstructure and the length-to-diameter aspect ratio of the specimen. In the aged condition, when the microstructure has {alpha}-phase particles distributed along flow lines the {beta}-phase matrix, the alloy has the propensity for shear failure when deformed in compression in a direction parallel to the flow lines. In the solution-heat-treated condition, the microstructure consists of {beta} grains with athermal {omega} phase. In this condition, the alloy can be cold compressed to 75% reduction in height using specimens with aspect ratio of 1.125, but fails by shear for a larger aspect ratio of 1.5. Plastic deformation of the material occurs initially by single slip in most grains, but changes to multiple slip at true plastic strains larger than about 0.15. At a slow strain rate, the deformation is uniform, and the material work hardens continuously.

• Sponsoring Organization: USDOE
• OSTI ID: 271746
• Journal Information: Journal of Materials Engineering and Performance, Journal Name: Journal of Materials Engineering and Performance Journal Issue: 3 Vol. 5; ISSN 1059-9495; ISSN JMEPEG
• Country of Publication: United States
• Language: English

Related Subjects

33 ADVANCED PROPULSION SYSTEMS
36 MATERIALS SCIENCE
AEROSPACE INDUSTRY
AGING
ALUMINIUM ALLOYS
AUTOMOBILES
CHEMICAL COMPOSITION
COMPRESSION STRENGTH
IRON ALLOYS
MATERIALS
MICROSTRUCTURE
MOLYBDENUM ALLOYS
PARTICULATES
PLASTICITY
PRECIPITATION
SLIP
STRAIN HARDENING
STRAIN RATE
STRAINS
STRESSES
TITANIUM BASE ALLOYS