MULTI-LAYER PIEZOELECTRIC ELEMENT, METHOD FOR MANUFACTURING THE SAME

摘要

A multi-layer piezoelectric element that has high durability with capability to operable continuously under higher voltage and higher pressure over a long period of time, a method for manufacturing the same, an injection apparatus and a fuel injection system are provided. The multi-layer piezoelectric element, comprising:
a multi-layer structure comprising a plurality of internal electrode layers and a plurality of piezoelectric material layers, the plurality of piezoelectric material layers being stacked with each one of the plurality of internal electrode layers intervened between each two of the plurality of piezoelectric material layers,
wherein a cross-sectional area of a cross section of the multi-layer structure parallel to the plurality of internal electrode layers is smaller in both end portions in a stacked direction than in a middle portion in the stacked direction.