Electrical, X‐Ray, and Thermal Expansion Studies in the System KNbO 3 ‐AgNbO 3

Unlike the KNbO 3 ‐NaNbO 3 system, the KNbO 3 ‐AgNbO 3 system possessed a very limited degree of solid solution between its end‐members. Solid solution of AgNbO 3 in KNbO 3 was limited to slightly less than 6 mole %, and solid solution of KNbO 3 in AgNbO 3 was limited to less than 0.5 mole %. Because of a tendency for the K 1‐ x Ag x NbO 3 system to lose oxygen spontaneously during firing when 0.06 ≤ x ≤ 0.995, the system could not be treated as a true binary system. The compositions in the KNbO 3 solid solution region (0 ≤ x < 0.06) were ferroelectric at room temperature. Lattice parameter, relative permittivity, and thermal expansion measurements were made on specimens in the region 0 ≤ x ≤ 0.06.