Light scattering by residual pores in transparent zirconia ceramics

We studied the effects of residual pores on the transparency of cubic zirconia ceramics by applying Mie scattering theory. The optical haze value H, defined as the diffuse transmission divided by the total forward transmission, was calculated as a function of the pore size (rpore) and the porosity of residual pores (Vpore) with sample thickness (t) = 1 mm. Even a small amount of pores critically affect the transparency; Vpore < 5 ppm is required to maintain H value within 1%, when rpore = 0.05 µm is assumed. The theoretical study also revealed that the acceptable amount of residual pores for H = 1% gradually degreases with an increase in the refractive index of the materials.