ENHANCED MANUFACTURING TECHNIQUE OF CELLULAR GLASS-CERAMIC USING THE MICROWAVE ENERGY

Abstract

The paper presents experimental results aiming the enhanced manufacturing technique of cellular glass-ceramic using a mixed microwave heating method (predominantly direct and partially indirect).  A SiC and Si₃N₄ ceramic tube with a wall thickness of 3 mm was used as a screen placed between the microwave radiation source and the material subjected to heating. The optimal sample was made by sintering at 980 ºC of 87.5% glass waste, 9.5% coal ash, 3% silicon carbide and 10% water addition. The product had the apparent density of 0.24 g/cm³, porosity of 88%, thermal conductivity of 0.052 W/m·K and compressive strength of 1.25 MPa. The material microstructure was homogeneous, with pores uniformly distributed, having the size between 0.4-1.2 mm.