Microplasticity in vanadium single crystals. [Activation parameters, 125 to 300/sup 0/K]

Journal Article · Fri Oct 01 04:00:00 EDT 1976 · Acta Metall.; (United States)

DOI:https://doi.org/10.1016/0001-6160(76)90041-9· OSTI ID:7215773

Crowe, C R ^[1]; Arsenault, R J

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1. Univ. of Maryland, College Park

An investigation of the activation parameters for plastic deformation in the microstrain region was performed. Vanadium single crystals with (491) axial orientations were tested in compression by strain rate cycling at various intervals over the strain range of 1 x 10/sup -5/ to 2 x 10/sup -3/ at a strain sensitivity of 5 x 10/sup -7/. Tests were conducted between 125 and 300 K on a series of crystals containing interstitial solute concentrations in the range 486 at. ppM to 1649 at. ppM oxygen plus nitrogen content. The results indicate that in the microstrain region more than one dislocation process is occurring. The results are consistent with the theory that edge and nonscrew dislocations are the mobile species in the microstrain region at low temperatures. As deformation proceeds, the mobile densities of the edge and nonscrew segments decrease and the transition to macroflow is associated with the onset of screw dislocation motion. The data indicate that in the microstrain region edge and nonscrew dislocation mobility is strongly affected by solute interactions. In the macrostrain regions, however, flow rate is apparently controlled by screw dislocation--lattice interactions. 13 figures, 1 table.

• OSTI ID: 7215773
• Journal Information: Acta Metall.; (United States), Journal Name: Acta Metall.; (United States) Vol. 24:10; ISSN AMETA
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360103* -- Metals & Alloys-- Mechanical Properties
COMPRESSION
CRYSTAL DEFECTS
CRYSTAL LATTICES
CRYSTAL STRUCTURE
CRYSTALS
DEFORMATION
DISLOCATIONS
EDGE DISLOCATIONS
ELEMENTS
ENTHALPY
FLOW STRESS
INTERACTIONS
LINE DEFECTS
LOW TEMPERATURE
MECHANICAL PROPERTIES
MEDIUM TEMPERATURE
METALS
MONOCRYSTALS
PHYSICAL PROPERTIES
PLASTICITY
SCREW DISLOCATIONS
STRESSES
TEMPERATURE DEPENDENCE
THERMODYNAMIC PROPERTIES
TRANSITION ELEMENTS
VANADIUM