THE PROCESSING OF CORDIERITE GLASSES CONTAINING ALN

Although cordierite glasses (2MgO . 2Al(2)O(3) . 5SiO(2)) have been st udied by normal glass processing route, little information is availabl e on the processing of cordierite glass containing high nitrogen conte nt. The main thrust of this programme is to study the formability of t he materials into useful glass ceramics particularly for electronics a nd precision structural parts. In this study, the melting, glass formi ng, nucleation and crystallisation characteristics of glasses containi ng up to 5% wt. nitrogen have been carried out. Combined heat flux dif ferential scanning calorimetry (DSC) and thermogravimetric analysis ha ve been used to study the reaction kinetics, melting endotherm, nuclea tion and crystallisation behaviour. The effect of the aluminium nitrid e on the stability of the melt, microstructures, and the container mat erials are presented and discussed. XRD and SEM techniques have been u sed to identify the phases developed, and the morphology of the comple x microstructures evolved.