BULK MODULUS AND YOUNGS MODULUS OF NANOCRYSTALLINE GAMMA-ALUMINA

Compression measurements mere performed for the first time on nanocrys talline gamma-alumina utilizing a diamond anvil cell (DAC) and the ene rgy dispersive X-ray diffraction method. The cubic unit cell (a = 0.79 24 nm) for gamma-alumina Tvas found to have a volume compression of ab out 2.4% over the pressure range from ambient to 3.8 GPa at room tempe rature under both hydrostatic and nonhydrostatic conditions. Using the first-order Bridgman equation and the Birch equation of state, the is othermal bulk modulus (B-0) mas determined to be 162 +/- 14 GPa and Yo ung's modulus (E) was estimated to be 253 +/- 22 GPa assuming a Poisso n's ratio for gamma-alumina of 0.24 +/- 0.2.