Piezoelectric element and process for production thereof

A method for producing a piezoelectric element comprising the steps of:

• superposing a piezoelectric material containing a Pb(Mg, Ni)1/3Nb2/3O3—PbZrO3—PbTiO3 ternary system solid solution composition represented by the following general formula (1) as a main component on a ceramic substrate or on an electrode formed on the ceramic substrate, and
• subjecting the superposed piezoelectric material to a thermal treatment in an atmosphere;
• wherein a previously heat-treated container and a previously heat-treated setter are used as a container for housing said electrode on which the piezoelectric material is superposed and a setter for mounting the piezoelectric material thereon in the presence of 0.03-0.5 mg/cm3 (NiO conversion amount per unit volume of a space in a container) of an atmosphere-controlling material having the same composition as the piezoelectric material
• Pbx{(Mg1−yNiy)1/3x aNb2/3}bTicZrdO3 (1)
• wherein 0.95≦x≦1.05;
• 0.05≦y≦0.20;
• 0.90≦a≦1.10;
• b, c and d are decimals falling in a range surrounded by (b,c,d)=(0.550, 0.425, 0.025), (0.550, 0.325, 0.125), (0.375, 0.325, 0.300), (0.100, 0.425, 0.475), (0.100, 0.475, 0.425) and (0.375, 0.425, 0.200), in the coordinates with coordinate axes of said b, c and d, and b+c+d=1.000.