Multilayer piezoelectric ceramic and method for manufacturing same, multilayer piezoelectric element, as well as piezoelectric vibration apparatus

A multilayer piezoelectric ceramic constituted by piezoelectric ceramic layers stacked alternately with internal electrode layers, wherein:

• the piezoelectric ceramic layers do not contain lead as a constituent element, and have a perovskite compound expressed by a composition formula LixNayK1-x-yNbO3 (where 0.02<x≤ 0.1, 0.02<x+y≤1), as a primary component;
• and
• the internal electrode layers are constituted by a metal containing silver by 80 percent by mass or more, and contain ceramic grains containing same elements found in the primary component,
• wherein the piezoelectric ceramic layers contain, with respect to 100 mol of the primary component:
• 0.2 to 3.0 mol of Li;
• 0.2 to 5.0 mol of at least one type of alkali earth metal element selected from a group that includes Ca, Sr, and Ba;
• 0.2 to 2.0 mol of Mn;
• and
• 0.1 to 3.0 mol of Si,
• wherein a ratio of a maximum value of diffraction intensity (Imax) to a minimum value of diffraction intensity (Imin), or (Imax/Imin), at 2θ=25.5° to 26.5° is 5.5 or greater but 8.0 or smaller as measured by an X-ray diffraction measurement using Cu-Kα rays performed on a surface of the piezoelectric ceramic layer positioned at the topmost surface in a stacking direction, wherein there is a peak of diffraction intensity at 2θ=25.5° to 26.5°, and the peak corresponds to the maximum value (Imax).