| 摘要 |
[Problem] Conventional multi-layer piezoelectric element sometimes cannot be stably driven because crack sometimes occurs in a stacked body when an amount of displacement is large and when being driven at high speed. [Solution] A multi-layer piezoelectric element (1) includes a stacked body (5) in which piezoelectric layers (2) and internal electrode layers are alternately laminated and a stress relaxing layer (4) is disposed at part of portions between the piezoelectric layers (2), and an external electrode (6) configured to bond to a side face of the stacked body so as to make electrical connection with the internal electrode layers, wherein the internal electrode layers are not exposed on the side face of the stacked body (5), but the stress relaxing layer (4) exposes on the side face of the stacked body (5). It is possible to selectively cause a crack caused by stress that is generated by extension and contraction of the stacked body, in the stress relaxing layer (4), and therefore the stress can be relaxed to suppress the occurrence of a short circuit between the internal electrode layers caused by the crack and achieve high displacement. |
