... is usually no pressing and sintering, glass-ceramics have, unlike sintered ceramics, no pores.A wide variety of glass-ceramic systems ... exists, e.g., the Li2O x Al2O3 x nSiO2-System (LAS-System), the MgO x Al2O3 x nSiO2-System (MAS-System), the ... ZnO x Al2O3 x nSiO2-System (ZAS-System). Work ...