| 摘要 |
PURPOSE:To enhance inner stress applied in a sample and to yield bending breakdown accompanying dynamic load fatigue in an early period, by imparting a static load to the sample such as ceramics with a second piezoelectric laminate, and imparting the dynamic load with a first piezoelectric body. CONSTITUTION:A compressing end 17 is brought into contact with the center of a sample (w) on a supporting edge 9. An AC voltage having a specified frequency is applied to a piezoelectric laminated body 2 from an output source 18 having AC waves such as pulse waves. A specified DC voltage is applied on a piezoelectric laminate 12 from a DC power source 15. Thus a specified static load is imparted to the compressing end 17 on the upper surface of the sample (w). Expansion and contraction are yielded in the piezoelectric laminated body 2 against a belleville spring 8 based on the AC wave. The peripheral part of the sample (w) is periodically compressed with the supporting edge 9. Therefore, the center of the sample (w) is compressed downward and the peripheral part is compressed upward. Thus deflection strain is yielded. The amount of the strain is read with a strain gage 16.
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