Preparation of yttrium aluminum garnet nano-powder and transparent ceramic by a modified co-precipitation method

The transparent ceramic of yttrium aluminum garnet (YAG) were successfully prepared by a modified co-precipitation method. The effect of precipitator/metal salt solution mole ratio on synthesis of YAG nano-powders and molding pressure on ceramic sintering process were studied. The samples were characterized by the X-ray diffraction (XRD) and field emission scanning electron microscope (FESEM) measurements. The results showed that when the mole ratio of NH4HCO3/([Al3+]+[Y3+]) is 8, the pure cubic YAG powder with averageparticle size of about 65 nm was obtained by calcining the precursor prepared by the modified method at 1000°C for 2 h. With the prepared YAG powders as raw material and tetraethyl orthosilicate as sintering additive, the YAG green bodys were formed under 100 MPa, and then YAG transparent ceramic was prepared by sintering YAG powder at 1750°C for 15 h in vacuum.