| Abstract Scope |
The growing demand for affordable electrical insulation materials has increased interest in utilizing indigenous ceramic resources as alternatives to imported porcelain. This study developed low-voltage ceramic electrical insulators from locally sourced Numan white ball clay, Alkaleri kaolin, Sahel granite dust, and Numan red ironstone from Northeastern Nigeria. Raw materials were characterized using X-ray fluorescence (XRF), while ceramic bodies and glazes were formulated using the triaxial blending approach and Seger unity formula, respectively. Specimens were shaped, dried, bisque-fired, glazed, and sintered at 1250 °C before physical, mechanical, electrical, thermal, and chemical evaluation. The optimized ceramic exhibited 7–8% linear shrinkage, 2.11 g/cm³ bulk density, 5.59% water absorption, and 11.80% apparent porosity. The dielectric constant ranged from 6.12 to 6.53, electrical resistivity from 1.60 × 10⁵ to 4.37 × 10⁵ Ω•m, and DC breakdown voltage reached 18 kV. Thermal conductivity was 1.099 W•m⁻¹•K⁻¹, while no visible deterioration was observed after chemical exposure. The results demonstrate the potential of indigenous Nigerian raw materials for low-voltage ceramic insulation, while the relatively high open porosity indicates scope for further densification. |