Microstructural evolution during superplastic deformation in large-grained iron aluminides

Conference · Thu Jul 01 04:00:00 EDT 1999

OSTI ID:20001651

Lin, T L; Liu, Y

Superplastic behavior has been found in Fe{sub 3}Al and FeAl alloys with grain sizes of 100--600{micro}m. The large-grained Fe{sub 3}Al and FeAl alloys exhibit all deformation characteristics of conventional fine size superplastic alloys. However, superplastic behavior was found in large-grained iron aluminides without the usual pre-requisites for superplasticity of a fine grain size of large-grained iron aluminides decreased during superplastic deformation. Transmission electron microscopy (TEM) observations have shown that there were a great number of subgrain boundaries which formed a network and among which the proportion of low and high angle boundaries increased with increased strain. The observed superplastic phenomenon is explained by continuous recovery and recrystallization. During superplastic deformation, an unstable subgrain network forms and these subboundaries absorb gliding dislocations and transform into low and high angle grain boundaries. A dislocation glide and climb process accommodated by subboundary sliding, migration and rotation, allows the superplastic flow to proceed.

• Research Organization: Shanghai Jiao Tong Univ. (CN)
• Sponsoring Organization: National Natural Science Foundation of China
• OSTI ID: 20001651
• Report Number(s): CONF-981104--; ISBN 1-55899-458-0; ISSN 1067-9995
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALUMINIUM ALLOYS
DATA
DISLOCATIONS
INTERMETALLIC COMPOUNDS
IRON ALLOYS
METALLOGRAPHY
MICROSTRUCTURE
PLASTICITY
TITANIUM ALLOYS