Research On PZT SMART Layer Used In Structural Health Monitoring

PZT SMART Layer is a thin film that having been compounded by a distributed sensor/actuator network and insulated carrier film making use of improved Flex Print circuit technique in advance. During the manufacture of composite, we can imbed the SMART Layer into its inner part, which the SMART Layer can not only monitor the manufacturing process of composite, but also can carry out real time, on-line monitoring for composite in service. In this text, we having mainly researched into the manufacturing, electrical performance of the PZT SMART Layer, and the influencing on mechanical performance of composite, the identifying of load etc. Therefore, these researches in this text have an important influence on carrying out real time, on-line structural health monitoring making use of PZT SMART Layer. In this text, first, we have made some appropriate improvement researches to the production craft of the Flex Print circuit at present, have manufactured PZT SMART Layer and composite mechanics experiment specimen embedded SMART Layer that regarding it as an additional layer; The second, through the research of imbedding SMART Layer has influenced on mechanical performance of composite, it has been confirmed by three groups contrasting experiment that the influence to composite axial tension strength, flatwise tension strength and compression strength is within the dispersing scope of composite manufacturing craft. Therefore, the result shows that even imbedding SMART Layer in glass fiber composite, the influence on mechanical performance of composite is negligible; The third, we have chosen the center frequency of actuator signal that is appropriate for the material in the research, and have researched electricial performance of PZT SMART Layer, such as the stability along with time, the stability of loading and after loaded, the consistency of sensors. In a word, from the above mentioned results of mechanical and electrical performance, we can conclude that PZT SMART Layer can be imbedded in composite and carry out health monitoring; The fourth, we have carried on identifying of tensional load making use of PZT SMART Layer. By the contrasting experiment, we have first discovered that PZT SMART Layer has more favorable linear relation of signal maximum magnitude – load and repeatability than PZT, and the trend that signal MAX. magnitude changes along with loading(or unloading) is opposite, this new detection still need to be further interpretative; The fifth, we have designed and manufactured PZT SMART Layer aimed at carbon fiber composite board strengthened with tendon of aerofoil box. and have also made a speculation that preliminary realizing the identifying of load in aerofoil box using PZT SMART Layer. This topic acquired the national natural science fund item (90205031) "the research of the SMART Layer"...