6. Conclusion

Ceramics and glasses are complex materials, both in terms of structure and microstructure. Ceramics are multiphase materials in which a "long-range" order (several crystal lattices) in three dimensions prevails. The domain of crystalline coherence in a ceramic is called the "grain", hence the notion of polycrystalline material. In glasses, an order can only be described at very short distances (a few Å), which precludes the existence of properties linked to a crystal lattice.

What distinguishes glass from ceramics is that :

• These are materials made up of grains, each characterized by its own crystalline structure, separated by grain boundaries. These grains do not necessarily all have the same physical properties (electrical, mechanical, etc.). The respective proportions of these phases and the way in which they are...