Piezoelectric ceramics, manufacturing method for piezoelectric ceramics, piezoelectric element, vibration device, and electronic device

A single-piece piezoelectric ceramic comprising as a main component a perovskite-type metal oxide represented by a compositional formula of ABO3,

• wherein an A site element in the compositional formula contains Ba and M1, the M1 being formed of at least one of Ca and Bi, where a ratio x of a molar amount of Ca to a total molar amount of Ba, Ca, and Bi is 0≤x ≤0.12, and a ratio y of a molar amount of Bi to the total molar amount of Ba, Ca, and Bi is 0≤y≤0.005,
• wherein a B site element in the compositional formula contains T1 and M2, the M2 being formed of at least one of Zr, Sn, and Hf, where a ratio 1 of a molar amount of Zr to a total molar amount of Ti, Zr, Sn, and Hf, a ratio m of a molar amount of Sn to the total molar amount of Ti, Zr, Sn, and Hf, and a ratio n of a molar amount of Hf to the total molar amount of Ti, Zr, Sn, and Hf are, respectively, 0≤1≤0.08, 0≤m≤0.03, and 0≤n≤0.08,
• wherein concentrations of the M1 and the M2 change in at least one direction of the piezoelectric ceramic, and
• wherein increase and decrease directions of concentration changes of the M1 and the M2 are directions opposite to each other.