When an electric field is applied to the electrodes the piezoelectric material translates this into a mechanical strain along its radial axis, causing it to vibrate.
当两个电极之间形成电场时，压电性物质便将电场转化为沿径向轴的机械压力，使纤维震动。
2
The field is radial.
场是散射状的。
3
It is found that in lined ceramic the radial cracks is caused by compressive stress field and net cracks caused by heat stress field.