Bereiding en eigenschappen van translucent gamma-aluminium oxynitride

The phase diagram of the Al2O3-AlN system in the vicinity of the Alon phase field was established, and Alon was found to be unstable below 1640 Deg; below this temp., Alon could be stabilized by adding MgO. Translucent Alons contg. 67.5, 73, and 77.5 mol% Al2O3 were prepd., and a no. of elec., optical, and mech. properties of these Alons were measured. [on SciFinder (R)

Mechanical properties of gamma-aluminium oxynitride

Mech. properties have been measured of three compositionally different types of g-aluminum oxynitride (Alon). The compns. corresponded to 67.5, 73 and 77.5 mol% Al2O3. To characterize the Alons, lattice parameters, densities, grain sizes and optical properties were measured. The measurements for the mech. properties comprise hardness at various indentation loads, elastic properties, fracture strength and fracture toughness (at room temp. and at 600 DegC). [on SciFinder (R)

Neutron diffraction of γ-aluminium oxynitride

Neutron diffraction expts. were performed on Al oxynitride (Alon) powders with compns. corresponding to 67.5, 73 and 77.5 mol.% Al2O3. The 73 mol.% powder was produced by reacting Al2O3 and AlN powders for 3 h at 1750 Deg. After reaction the resultant powder was ground with a mortar and pestle to eliminate large particles. X-ray diffraction (XRD) of the powder revealed that residual AlN was present. The Alon structure can be described with the const.-anion model. In this case the vacancies in the cation lattice are located almost completely at octahedral sites in the lattice. Neutron diffraction yields approx. the same lattice parameter for the Alons as XRD: 0.7953, 0.7944 and 0.7938 for Alon with a compn. of 67.5, 73 and 77.5 mol.% Al2O3, resp. The spinel parameter of Alon is not or is not very weakly dependent on the compn. of the Alon and is approx. equal to 0.3812. [on SciFinder (R)