Effect of milling time and microwave sintering on microhardness and electrical properties of nano and micro structured cordierite


1 Ceramic Department, Materials & energy Research Centre

2 Ceramic , Merc


The purpose of this research is to investigate the mechanical and electrical properties of nano structured cordierite. Nano grain size powders were synthesized through mechanical activation by high-energy ball milling of the starting powders containing 34.86 wt% Al2O3, 51.36 wt% SiO2, and 13.78 wt% MgO. Samples were prepared by conventional and microwave sintering at 1390°C. SEM observations illustrated the equiaxed nano-grains of cordierite with an average grain size of 40 nm for samples sintered in microwave. With the increase of milling time, samples sintered at 1390°C in microwave furnace obtained higher micro-hardness and density than those sintered at the same temperature in conventional furnace. Sample milled for 30 h and sintered in microwave furnace at 1390°C obtained the maximum dielectric constant of 5.5±0.1.