Development of new and high performance piezoelectric smart devices having multifunctionality

在本研究中，开发了一种内嵌电极的新型压电陶瓷纤维铝基复合材料，实现了多功能、高性能的压电器件，取得了以下成果：1. 采用相形成/键合的方法可以将脆性金属芯压电纤维嵌入铝基体中而不造成损伤。利用该方法，可以将加工过程中产生的残余合金填充到空心压电纤维中，形成其内部电极，并成功嵌入铝基体中。2. 由于该复合材料的极化电场关系产生了一个磁滞回线，可见嵌入的金属芯压电纤维作为压电材料工作。在振荡试验和冲击试验中产生的输出电压波形显示应变和冲击传感的可能性。3. 由于铝基复合材料在冲击试验中产生的响应波形优于树脂基复合材料。采用空心压电光纤的器件性能与采用金属芯压电光纤的器件性能相当。4. 通过改进制作工艺，可以去除薄型贴片型器件中嵌入的压电纤维周围的共晶合金残留和空隙，器件输出电压达到传统器件的6倍。5. 利用电子束云纹法对压电纤维的残余压应力进行了测量，结果表明，压电纤维承受了约1 Gpa的高压应力，并且表明，即使热处理去除残余压应力，残余压应力值也不会发生变化，不会干扰高输出电压的产生。

In this research, new aluminum matrix composites embedded with the piezoelectric ceramic fiber which have an internal electrode were developed to realize multifunctional and high performance piezoelectric devices, and the following results were obtained. 1. The brittle metal-core piezoelectric fiber can be embedded in aluminum matrix without damage by the interphase forming/bonding method. Using this method, hollow piezoelectric fiber can be filled with the residual alloy produced during the process to form its internal electrode as well as successful embedment in the aluminum matrix. 2. As the poling - electric field relationship of this composite generates a hysteresis loop, it is clear that the embedded metal-core piezoelectric fiber is working as piezoelectric material. The waveform of the out-put voltage generated in the oscillation test and the impact test shows the possibility of strain and impact sensing. 3. As the responding waveform generated in the impact test of the aluminum matrix composite is superior to that of the resin matrix one. The performance of the device using the hollow piezoelectric fiber is as good as the one using the metal-core piezoelectric fiber. 4. The residuals of eutectic alloy and voids around the embedded piezoelectric fiber produced in the thin and patch type device can be removed by modification of the fabrication process, and the output voltage of this device reaches 6 times of that of the conventional one. 5. The compressive residual stress working on the embedded piezoelectric fiber was evaluated using the electron beam moire method, and it was shown that the piezoelectric fiber is subjected to a very high compressive stress of about 1 Gpa, and was also shown that the very high and isotropic residual stress doesn't disturb generation of the high output voltage because the value did not change even after removal of if by heat treatment.