Plastic Deformation of Wadsleyite and Olivine at High-Pressure and High-Temperature using a Rotational Drickamer Apparatus (RDA)

Journal Article · Tue Jan 01 00:00:00 EST 2008 · Physics of the Earth and Planetary Interiors

DOI:https://doi.org/10.1016/j.pepi.2008.03.003· OSTI ID:980391

Nishihara, Y; Tiner, D; Kawazoe, T; Xu, Y; Jing, Z; Matsukage, K; Karato, S

Large-strain plastic deformation experiments of wadsleyite and olivine were conducted using a rotational Drickamer apparatus (RDA) up to pressure and temperature conditions corresponding to the Earth's mantle transition zone. Sintered ring-shaped (Mg,Fe)2SiO4 wadsleyite and olivine samples were deformed at P not, vert, similar 16 GPa and T = 1600 and 1800 K, and P not, vert, similar 11 GPa and T = 1800 K, respectively, with equivalent strain rate of View the MathML source. In situ observations of deforming samples were carried out using the synchrotron radiation facility at Brookhaven National Laboratory, NSLS, X17B2. Stress was measured by X-ray diffraction at six different angles with respect to the compression axis. The stress estimated by X-ray diffraction was in good agreement with the stress estimated from dislocation density (for olivine). Strain was determined using X-ray radiographs of a strain marker (Re or Mo foil). Deformation of samples with a RDA involves both uniaxial compression and simple shear. A new formulation is developed to analyze both components to determine the rheological properties of a sample. Stress-strain curves show strain-hardening up to the equivalent strain of var epsilonE not, vert, similar 0.2 followed by the quasi-steady state deformation. Wadsleyite is found to be stronger than olivine compared at similar conditions and the creep strength of olivine at P not, vert, similar 11 GPa is much higher than those at lower pressures.

• Research Organization: Brookhaven National Lab. (BNL), Upton, NY (United States). National Synchrotron Light Source
• Sponsoring Organization: Doe - Office Of Science
• DOE Contract Number: DE-AC02-98CH10886
• OSTI ID: 980391
• Report Number(s): BNL-93309-2010-JA; PEPIAM; TRN: US1005487
• Journal Information: Physics of the Earth and Planetary Interiors, Vol. 170; ISSN 0031-9201
• Country of Publication: United States
• Language: English

Related Subjects

43 PARTICLE ACCELERATORS
BNL
COMPRESSION
CREEP
DEFORMATION
DENSITY
DIAGRAMS
DISLOCATIONS
EQUIPMENT
IMAGES
NSLS
OLIVINE
PLASTICS
PRESSURE RANGE MEGA PA 10-100
SHEAR
STRAIN HARDENING
STRAIN RATE
STRAINS
SYNCHROTRON RADIATION
TEMPERATURE RANGE 0400-1000 K
X-RAY DIFFRACTION
national synchrotron light source