Abstract
We have reported that Ca-α sialon hollow ball with 200-500nm in diameter which is composed of very fine particles with 10-30nm in diameter could be synthesized by carbothermal reduction-nitridation method. In this study, the porous Ca-α sialon was produced from the Ca-α sialon hollow through the spark plasma sintering (SPS) method. SPS was carried out at the temperature of 1650 to 17000C for 1 min in 0.1MPaN2under uniaxial pressing at 5MPa. It was confirmed that the porous Ca-α sialon ceramics was obtained. The shape of hollow ball remained after sintering to have bimodal pore size distribution which corresponded to the size of hollow balls and the space between primary grains.The strength of the porous material was found to be higher than conventional porous alumina ceramics with the same porosity.
