Light scattering in MgO-doped alumina fabricated by spark plasma sintering

The microstructure and optical properties of MgO-doped alumina fabricated by spark plasma sintering were investigated. MgO doping to alumina exhibited no noticeable effect on the total forward transmission, but suppressed grain growth and enhanced in-line transmission. The analytical investigation of the scattering coefficients confirmed that MgO-doped alumina has the scattering characteristics of the homogeneous matrix dispersed with spherical scattering grains, and that the existing model of light scattering in an alumina polycrystal is valid within a limited range of the wavelength/grain size ratio. The investigation also led to experimental determination of the effective volume density of spherical scattering grains satisfying the Rayleigh–Gans theory.