Deformation behavior and dislocation mechanisms in TiAl alloys

Book · Tue Aug 01 04:00:00 EDT 1995

OSTI ID:78388

Sriram, S; Vasudevan, V K ^[1]; Dimiduk, D M ^[2]

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1. Univ. of Cincinnati, OH (United States). Dept. of Materials Science and Engineering
2. Wright Lab., Wright-Patterson AFB, OH (United States)

Polycrystalline Ti-50 and Ti-52Al (in at.%) alloys, with large grain sizes (50Al-300{mu}m, 52Al-500{mu}m) and containing low ({approximately}250 wt.ppm) levels of oxygen were deformed under compression over a wide temperature range (77--1,173 K). The 0.2% proof stress-temperature profiles comprise of three distinct regimes: Regime 1 (between 77--{approximately}600 K), regime 2 (between {approximately}600--1,073 K), and regime 3 (above 1,073 K). Deformation temperature influences the types of dislocations present, the nature of superdislocation dissociations, and the morphological characteristics of both ordinary and super dislocations. Collectively, experiment and theory suggest that the flow properties at low temperatures (regime 1) are controlled by lattice friction, whereas at higher temperatures (regime 2) the properties are dislocation obstacle controlled.

• OSTI ID: 78388
• Report Number(s): CONF-941144--; ISBN 1-55899-265-0
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALUMINIUM ALLOYS
DEFORMATION
DISLOCATIONS
EXPERIMENTAL DATA
FLOW STRESS
INTERMETALLIC COMPOUNDS
TEMPERATURE DEPENDENCE
TITANIUM ALLOYS