Characterization of a metal-core piezoelectric ceramics fiber/aluminum composite

Abstract

This paper describes the characterization of a metal-core piezoelectric ceramics fiber/aluminum composite as a metal-based piezoelectric composite. Piezoelectric materials, especially piezoelectric ceramics are generally used as excellent transducer materials. However, there are serious disadvantages, as they are very brittle and need a complicated electrode system with an adhesion layer to generate piezoelectricity. Therefore, the application of piezoelectric ceramics is limited. In order to solve these problems, a metal-core piezoelectric ceramics fiber/aluminum composite was developed. The metal-core piezoelectric fiber is not as brittle as bulk ceramics, but it is still too brittle to be embedded in an aluminum matrix using a conventional process. Therefore, the interphase forming/bonding method was applied to embed it in an aluminum matrix without fracture. Using this successful approach, a simple electrode system was formed between the metal core of the embedded fiber and the matrix. As this material system is expected to be used as a robust sensor and energy harvester, its output voltage and power characteristics were evaluated with vibration test equipment and compression vibration equipment. According to the results, the output voltage generated from the specimen is proportional to its strain, and dependent on its direction. It was also found that the output power generated from the specimen increases with the square of its strain, and in proportion to its frequency, and the calculated maximum output power reaches approximately 3.4 mW when the specimen undergoes 0.2 % strain and 600 Hz frequency by vibration. As this output power is generated from the single embedded fiber, it is suggested that the energy for driving a wireless module can be secured by embedding multiple fibers. Consequently, a composite embedded with multiple fibers will be able to be used as a wireless strain sensor owing to its strain measurement and energy-harvesting capabilities.

Keywords

• smart materials
• composite materials
• sensor
• energy conversion materials
• aluminum alloy