Do Reuss and Voigt Bounds Really Bound in High-Pressure Rheology Experiments?

Journal Article · Sun Jan 01 04:00:00 EST 2006 · J. Phys.: Condens. Matter

DOI:https://doi.org/10.1088/0953-8984/18/25/S11· OSTI ID:914166

Chen, J; Li, L; Yu, T; Long, H; Weidner, D; Wang, L; Vaughan, M

Energy dispersive synchrotron x-ray diffraction is carried out to measure differential lattice strains in polycrystalline Fe{sub 2}SiO{sub 4} (fayalite) and MgO samples using a multi-element solid state detector during high-pressure deformation. The theory of elastic modeling with Reuss (iso-stress) and Voigt (iso-strain) bounds is used to evaluate the aggregate stress and weight parameter, {alpha} (0{le}{alpha}{le}1), of the two bounds. Results under the elastic assumption quantitatively demonstrate that a highly stressed sample in high-pressure experiments reasonably approximates to an iso-stress state. However, when the sample is plastically deformed, the Reuss and Voigt bounds are no longer valid ({alpha} becomes beyond 1). Instead, if plastic slip systems of the sample are known (e.g. in the case of MgO), the aggregate property can be modeled using a visco-plastic self-consistent theory.

• Research Organization: Brookhaven National Laboratory (BNL) National Synchrotron Light Source
• Sponsoring Organization: Doe - Office Of Science
• DOE Contract Number: AC02-98CH10886
• OSTI ID: 914166
• Report Number(s): BNL--78734-2007-JA
• Journal Information: J. Phys.: Condens. Matter, Journal Name: J. Phys.: Condens. Matter Vol. 18; ISSN 0953-8984; ISSN JCOMEL
• Country of Publication: United States
• Language: English

Related Subjects

43 PARTICLE ACCELERATORS
DEFORMATION
NSLS
PLASTICS
RHEOLOGY
SLIP
STRAINS
SYNCHROTRONS
X-RAY DIFFRACTION
national synchrotron light source