Stereology Study of the Neodymium Doped Yttrium Aluminum Garnet (Nd:YAG) Transparent Ceramics

The neodymium doped yttrium aluminum garnet (Nd:YAG) powders were synthe- sized by the low temperature combustion and the transparent ceramic disks with 9mm in diameter and 1mm in thickness were prepared by the vacuum sintering at 1700℃for 5h after being 300MPa model pressing.The transparent ceramics were characterized by optical transmittance,field emis- sion gun-environment scanning microscope and the study were carried out on the qualitative rela- tionship between the optical transmittance and microstructure parameters using stereology theory and method.The results show that the optical transmittance of Nd:YAG transparent ceramics with 9mm in diameter and 1mm in thickness is about 45% in visible region and 55% in infrared region and increase with the incidence light wavelength increasing.The optical transmittance in- creases with three dimensionally corresponding diameter(D_(3S)) of grain climbing and reaches the theoretical value of single crystals when D_(3S) is 20μm.The optical transmittance decreases with the grain and single grain mean specific area enhancing and mean free distance of grains adding.