| 摘要 |
<p>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 ceramic layers,
wherein the multi-layer structure comprises a driving portion formed by stacking the plurality of internal electrode layers and the piezoelectric ceramic layers alternately on each other, and non-driving portions that are formed by stacking a plurality of the piezoelectric ceramic layers and are disposed on both end portions of the driving portion in a stacked direction, and
wherein the piezoelectric ceramic layers of the non-driving portions comprise the same piezoelectric material as that of the piezoelectric ceramic layers of the driving portion as a main component, and have a mean crystal grain size larger than that of the driving portion.</p> |
