Compression behavior of WC and WC-6%Co up to 50 GPa determined by synchrotron x-ray diffraction and ultrasonic techniques

Journal Article · Wed Jul 23 04:00:00 EDT 2008 · J. Appl. Phys.

DOI:https://doi.org/10.1063/1.2938024· OSTI ID:1006718

Amulele, George M; Manghnani, Murli H; Marriappan, Sekar; Hong, Xinguo; Li, Fengung; Qin, Xiomei; Liermann, Hanns P ^[1]

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1. Hawaii

The equations of state (pressure-volume relations) for WC and WC-6%Co have been determined by synchrotron x-ray diffraction measurements on polycrystalline powder samples loaded in a diamond anvil cell as well as by ultrasonic measurements on hot-pressed polycrystalline, cylindrical samples loaded in a multianvil high-pressure apparatus. The third-order Birch-Murnaghan equation of state fitted to the x-ray diffraction pressure-density sets of data, collected up to 50 GPa, yields ambient pressure isothermal bulk moduli of K{sub oT} = 411.8{+-}12.1 GPa and K{sub oT} = 402.4{+-}14.1 GPa, with pressure derivatives of K{sub oT}' = 5.45{+-}0.73 and K{sub oT}' = 7.50{+-}0.86 for WC and WC-6%Co, respectively. The ultrasonic measurements, conducted up to 14 GPa, enabled the determination of the pressure dependences of both bulk and shear moduli. Using Eulerian finite strain equations to fit the ultrasonic data, we obtain for WC an ambient pressure adiabatic bulk modulus of K{sub os} = 383.8{+-}0.8 GPa, and K{sub os}' = 2.61{+-}0.07 for its pressure derivative, while values of G{sub os} = 304.0{+-}0.3 GPa and G{sub os}' = 1.50{+-}0.09 were determined for the shear modulus and its pressure derivative, respectively. Meanwhile, for WC-6%Co, we obtain K{sub os} = 357.5{+-}1.0 GPa, K{sub os}' = 5.18{+-}0.14, G{sub os} = 253.5{+-}0.3 GPa, and G{sub os}' = 1.09{+-}0.09. The equations of state derived from the ultrasonic data are in good agreement with extrapolated results reported previously by Day and Ruoff [J. Appl. Phys. 44, 2447 (1973)] and Gerlich and Kennedy [J. Appl. Phys. 50, 3331 (1978)] who carried out measurements up to 0.2 and 1.0 GPa, respectively.

• Research Organization: Advanced Photon Source (APS), Argonne National Laboratory (ANL), Argonne, IL (US)
• Sponsoring Organization: USDOE
• OSTI ID: 1006718
• Journal Information: J. Appl. Phys., Journal Name: J. Appl. Phys. Journal Issue: 2008 Vol. 103; ISSN JAPIAU; ISSN 0021-8979
• Country of Publication: United States
• Language: ENGLISH

Related Subjects

36 MATERIALS SCIENCE
CERMETS
COBALT ALLOYS
COMPRESSIBILITY
COMPRESSION
DIAMONDS
EQUATIONS OF STATE
PRESSURE DEPENDENCE
PRESSURE RANGE GIGA PA
SHEAR
STRAINS
SYNCHROTRONS
TUNGSTEN ALLOYS
TUNGSTEN COMPOUNDS
ULTRASONIC WAVES
X-RAY DIFFRACTION