Effect of sintering on physical, mechanical, and electrical properties of alumina-based porcelain insulator using economic raw materials doped with zirconia

Increasing approachability of substitute materials for electrical ceramic porcelain insulator, research is requisite to adapt designs including porcelain raw materials to the current economic realities of the industry. This study aimed to analyze the effect of zirconia concentration (0, 2.5, 5, 7.5, and 10 wt.%) on the physical, mechanical, and dielectric properties of an alumina-based ceramic insulator. The pellets were prepared using the uniaxial pressure technique applying 160 MPa pressure. Different characterizations techniques such as XRD, dilatometer, and SEM used to identify the phase, thermal, and microstructural changes, respectively, of the sintered samples (1350 °C). Results indicated that alumina-based porcelain composition with 7.5 wt.% zirconia shows the maximum density of 2.63 g/cm3 with minimum water absorption of 0.18%. The average measured value of the coefficient of thermal expansion (αavg) for each sintered samples from 250 to 450 °C, and 1050 to 1250 °C is 8.254 × 10−6/ °C, and 7.16 × 10−6/ °C were observed, respectively. The highest bending (141 ± 5 MPa), compressive (216 ± 10), and tensile (40 ± 3 MPa) strength were also noted for the same composition. The value of dielectric, resistivity, and conductivity were also measured. From the result, it was concluded that low-cost raw materials with 7.5 wt.% zirconia-doped concentration yield the better physical, mechanical, and electrical properties with alumina-based electrical porcelain insulator.