Strengthening mechanisms, creep, and fatigue processes in dispersion-hardened niobium alloy. Final scientific report, 1 Feb 89-31 Jan 92

Technical Report · Mon Apr 20 00:00:00 EDT 1992

OSTI ID:5006129

Mukherjee, A K; Gibeling, J C

The creep and fatigue properties of pure Nb and Nb-l%Zr alloy were investigated. A model was developed based on the migration of subgrain boundary that can explain the anomalous primary creep transients found in Nb-l%Zr alloy, due to coarsening of subgrain structure. TEM investigations confirmed that such subgrain coarsening occurs during primary creep of Nb-l%Zr. Baseline low cycle fatigue studies of Nb and Nb-l%Zr were completed. Cyclic hardening is observed and there is a microplastic plateau in Nb. The Nb-1%Zr is stronger in cyclic deformation than Nb, with little influence of strain rate. The deformation in the alloy at both high and low strain rates is controlled by the interaction between gliding edge dislocation and solute atoms.

• Research Organization: California Univ., Davis, CA (United States). Div. of Materials Science and Engineering
• OSTI ID: 5006129
• Report Number(s): AD-A-250282/1/XAB; CNN: AFOSR-89-0287
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
NIOBIUM
MECHANICAL PROPERTIES
NIOBIUM ALLOYS
ZIRCONIUM ALLOYS
ALLOYS
CREEP
DEFORMATION
DISLOCATIONS
DISPERSIONS
FATIGUE
GRAIN BOUNDARIES
HARDENING
INTERACTIONS
METALS
MIGRATION
STRAIN RATE
STRESSES
TRANSIENTS
TRANSMISSION ELECTRON MICROSCOPY
CRYSTAL DEFECTS
CRYSTAL STRUCTURE
ELECTRON MICROSCOPY
ELEMENTS
LINE DEFECTS
MICROSCOPY
MICROSTRUCTURE
TRANSITION ELEMENTS
360103* - Metals & Alloys- Mechanical Properties