Much focus has been placed on piezoelectric materials composed of potassium sodium niobate having a perovskite crystal structure as lead-free piezoelectric ceramic compositions.
Japanese Unexamined Patent Application Publication No. 11-228227 discloses a piezoelectric ceramic composition containing a composition represented by a general formula: (1-n) (K1-x-yNaxLiy)m(Nb1-zTaz)O3-nM1M2O3 as a primary component wherein m, n, x, y, and z fall within the ranges 0.98≤m≤1.0, 0<n<0.1, 0.1≤x, y≤0.3, x+y<0.75, and 0≤z≤0.3.