Crystallization of MgO-Al/sub 2/O/sub 3/-SiO/sub 2/-ZrO/sub 2/ glasses

摘要: The crystallization of MgO-Al/sub 2/O/sub 3/-SiO/sub 2/-ZrO/sub 2/ glasses at 1000/sup 0/C was studied. Isothermal heat treatments a cordierite-based glass (2MgO.2Al/sub 3/.5SiO/sub equal to Mg/sub 2/Al/sub 4/Si/sub 5/O/sub 18/) with 7 wt% ZrO/sub produced surface ..cap alpha..-cordierite and tetragonal (t-ZrO/sub 2/). These phases advanced into the by cocrystallization t-ZrO/sub rods in an matrix well-defined orientation relation. were unstable respect diffusional breakup (a Raleigh instability) decomposed rows aligned ellipsoidal spheroidal particles. very resistant transformation monoclinic symmetry. With similar containing 15 2/, accompanied internal dendrites. Transformation dendrites symmetry observed under some conditions.