Development of new and high performance piezoelectric smart devices having multifunctionality

本研究开发了嵌入具有内电极的压电陶瓷纤维的新型铝基复合材料，以实现多功能、高性能的压电器件，并取得了以下成果。 1.通过相间成型/粘合方法，可以将脆性金属芯压电纤维无损伤地嵌入铝基体中。利用该方法，可以用过程中产生的残余合金填充中空压电纤维，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-电场关系产生磁滞回线，因此很明显嵌入的金属芯压电纤维充当压电材料。振荡测试和冲击测试中产生的输出电压波形显示了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。使用空心压电纤维的器件的性能与使用金属芯压电纤维的器件一样好。 4、薄型贴片式器件中产生的共晶合金残留和嵌入压电纤维周围的空洞可以通过改进制造工艺去除，并且该器件的输出电压达到传统器件的6倍。 5.使用电子束云纹法评估了嵌入压电纤维上的压缩残余应力，结果表明，压电纤维承受约1 Gpa的非常高的压缩应力，并且还表明，非常高且各向同性的残余应力不会干扰高输出电压的产生，因为即使在通过热处理去除IF后，该值也不会改变。

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.