PURPOSE: To obtain a compound piezoelectric material, which is capable of zeroing substantially various constants in some direction such as α31, α33 and αh directions, by a method wherein the piezoelectric material consists of a combination of two kinds of piezoelectric materials, which are made to differ from each other in coercive force, and the directions of polarization of these piezoelectric materials are oriented in the opposite direction to each other.

CONSTITUTION: A material, which has a large coercive force and a large anisotropy in a piezoelectric constant, such as powder 11 polarizable in a high DC electric field of 50kV/cm or higher like a titanate or the like, is used as the inorganic piezoelectric material on one side of inorganic piezoelectric materials and a material, which has a small coercive force and has a small anisotropy in the piezoelectric constant, such as powder 12 polarizable easily in a low DC electric field of 40kV/cm or lower like a barrium titanate or the like, is used as the other inorganic piezoelectric material. As the polarization directions of two kinds of these piezoelectric materials 11 and 12 are different from each other, their piezoelectric behaviors reach an opposite phase to each other and negate to each other. Accordingly, when constants in the directions α33 vertical to an electrode surface or the direction α31 parallel to the electrode surface are equal to each other, the constants zero and the direction α31 or the direction α33 of some one of constants, which are not equal to each other, becomes effective.