New [NZP] materials for protection coatings. Tailoring of thermal expansion

[NZP] (the NaZr2P3O12-Family) materials can be selected for synthesizing new thermal shock resistant ceramic coatings with a thermal expansion that can be tailored to match that of the substrate, and to possess a low thermal expansion anisotropy. The tailoring technique will involve the selection of a suitable pair of compositions which, upon being mixed to form a crystalline solution, will possess the desired thermal expansion coefficient and will have negligible thermal expansion anisotropy. This can be done when the axial thermal expansion for one end member is larger in the a-direction than in the c-direction and vice versa for the other end member. (C) 2000 Kluwer Academic Publishers.