Effect of Mechanical Milling Treatment on the Pressureless Sintering of KSr2Nb5O15

The effect of the mechanical milling treatment for calcined powders on the density of sintered materials was examined to prepare KSr 2 Nb 5 O 15 (KSN) dense ceramics under the pressureless condition. The milling treatment process is effective for preparation of dense KSN ceramics. The KSN ceramics having relative density up to 98.7% was obtained at 1300°C by pressureless sintering. Relative density of 96.3% was also shown in a ceramic sintered at 1250°C from the powder milled at a certain condition. Temperature dependence of dielectric constants showed very broad peak, indicating the nature of relaxor ferroelectrics.