Transformation-mismatch superplasticity in pure titanium and a titanium matrix composite

Book · Sun Dec 31 04:00:00 EST 1995

OSTI ID:194193

Bedell, C M; Zwigl, P; Dunand, D C ^[1]

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1. Massachusetts Inst. of Tech., Cambridge, MA (United States). Dept. of Materials Science and Engineering

Commercially-pure titanium containing 0 vol.% and 10 vol.% TiC particulates was thermally cycled about the allotropic transformation temperature of the matrix while being subjected to an external uniaxial tensile stress. Under these conditions, unreinforced titanium is superplastic, as evidenced by a high strain to fracture of 200% and a high strain-sensitivity exponent. The average strain per cycle is in good agreement with existing transformation-mismatch superplasticity models, based on the biasing by the external stress of the transformation mismatch stresses or stains. Transformation-mismatch superplasticity is also observed in the Ti-10% TiC metal matrix composite, which displays a strain to fracture of 135% and an average strain per cycle significantly higher than for unreinforced titanium. This novel effect is modeled by considering the increase in mismatch stresses in the composite, as a result of the inert TiC particles in the transforming titanium matrix.

• OSTI ID: 194193
• Report Number(s): CONF-950201--; ISBN 0-87339-300-7
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
COMPOSITE MATERIALS
CREEP
EXPERIMENTAL DATA
MATHEMATICAL MODELS
PHASE TRANSFORMATIONS
PLASTICITY
STRAIN RATE
STRAINS
STRESSES
THERMAL CYCLING
TITANIUM
TITANIUM CARBIDES