Piezoelectric Ceramic Fibers Research Articles

Fabrication of Pb(Nb,Ni)O3-Pb(Zr,Ti)O3 Piezoelectric Ceramic Fibers by Extrusion of a Sol-Powder Mixture

A study on the fabrication of Pb(Nb,Ni)O3-Pb(Zr,Ti)O3 (PNN-PZT) piezoelectric ceramic fibers by extrusion of a powder-sol mixture is presented. The process using extrusion of a powder-sol mixture was first applied to the fabrication of PZT fibers and its advantages were discussed in the former study. In this study, the process is applied to the fabrication of PNN-PZT fibers, and the conditions of the process, such as the viscosity adjustment of sol, the additives for suppressing hydrolysis reaction in the preparation of sol, the mixture ratio of powder and sol, and the sintering temperature, were investigated. The PNN-PZT sol functions as a binder during extrusion, but it changed into PNN-PZT crystalline during sintering so that the removal process of additives before sintering was not required. Green fibers with a diameter of about 250 mm were successfully extruded from the mixture of PNN-PZT sol and powder, with a sol to powder ratio between 1: 5 and 1: 8 (molar ratio). The microstructure, dielectric property and piezoelectric property of the fabricated fibers are investigated and compared with those of the fibers fabricated from a powder and organic binder mixture. The results show that the fibers sintered at 1200°C have good microstructure and exhibit competitive performance as the bulk material.

Integrated Active Fibre Composites Elements ForStructural Health Monitoring In Glass FibreReinforced Laminates

Active Fibre Composites (AFC) elements consist of piezoelectric ceramic fibres embedded between two interdigitated electrodes in a thermoset polymer matrix. A deformation of the piezoelectric AFC elements by external forces generates a voltage across the electrodes that can be recorded. Acoustic Emission (AE) analysis is a well established method for structural integrity monitoring of composite structures and elements. AFC elements can detect acoustic waves in structural elements analogous to conventional commercial AE sensors. Experimental results using AFC elements as AE sensors integrated into glass fibre reinforced epoxy (GFRP) laminates and polymethyl methacrylate (PMMA) plates are presented. Their AE sensor properties are compared for three coupling conditions: a) integrated into the test plates, b) permanently bonded on the surface of the test plates, and c) reversibly mounted on the plates. The performance of the AFC elements in case c) is also compared with that of reversibly mounted commercial AE sensors. The sensitivity of the AFC elements is higher along the direction of the piezoelectric fibres than normal to it and at least comparable or slightly higher than that of the reversibly mounted conventional AE sensors. A definite increase in sensitivity is achieved by bonding and integration. Further, the results show that integrated and/or bonded AFC elements fulfil the basic requirements for use in the structural health monitoring of composite structures.

Actuator Performance Degradation of Piezo-Composite Actuator LIPCA under Cyclic Actuation

This paper is concerned with the fatigue characteristics of LIPCA (LIghtweight Piezo-Composite Actuator) device system. LIPCA device system is composed of a piezoelectric ceramic layer and fiber reinforced light composite layers, typically a PZT ceramic layer is sandwiched by a top fiber layer with low CTE (coefficient of thermal expansion) and base layers with high CTE. The advantages of the LIPCA design are using the lightweight fiber reinforced plastic layers without compromising the generation of high force and large displacement and to have design flexibility by selecting the fiber direction and the size of prepreg layers. In addition to the lightweight advantage and design flexibility, the proposed device can be manufactured without adhesive layers when we use resin prepreg system. To investigate the degradation of actuation performance of LIPCA due to the repeated fatigue loading, the repeated loading tests up to several million cycle were performed and the actuation displacement for a given excitation voltage was measured during the test. The fatigue characteristics was measured using an actuator test system consisted of an actuator supporting jig, a high voltage actuating power supplier, and a non-contact laser measuring system and evaluated.

Promising compact wavelength-tunable optical add-drop multiplexer in dense wavelength-division multiplexing systems.

We design and model a highly compact and tunable optical add-drop multiplexer (OADM) device that consists of long-period gratings and piezoelectric ceramic fiber stretchers. The proposed OADM shows that 50 dense wavelength-division multiplexing channel signals can be selected in the wavelength range from 1526.25 to 1563.75 nm with 0.75-nm channel spacing, which covers the whole C-band gain spectrum of an erbium-doped fiber amplifier. The cross talk between channels is less than -39 dB, and the total insertion loss of the device is approximately 0.24 dB, which includes the splicing losses, the mode mismatching loss, and the expected losses in the two side-by-side coupled fibers.

Fabrication and Applications of Piezoelectric Ceramic Fibers with a Metal Core(International Workshop on Smart Materials and Structural Systems, W03 Jointly organized by Material & Processing Division, Material & Mechanics Division, Dynamics & Control Division and Space Engineering Division.)

Fabrication and Applications of Piezoelectric Ceramic Fibers with a Metal Core(International Workshop on Smart Materials and Structural Systems, W03 Jointly organized by Material & Processing Division, Material & Mechanics Division, Dynamics & Control Division and Space Engineering Division.)

Fabrication of piezoelectric ceramic fibers by extrusion of Pb(Zr, Ti)O3 powder andPb(Zr, Ti)O3sol mixture

In this study, Pb(Zr, Ti)O3(PZT) piezoelectric ceramic fibers were fabricated by extrusion from amixture of PZT powder and PZT sol. The added PZT sol in this studyplayed the role of a binder; the sol changed into crystalline PZT duringsintering, and removal of additives before sintering was not required. Toobtain the required PZT fibers, the sol viscosity adjustment condition, themixture ratio of powder and sol for fiber extrusion, and the sinteringcondition for obtaining polycrystalline fibers were investigated. The PZTprecursor solution was synthesized from lead acetate trihydrate, zirconiumn-propoxide,and titanium isopropoxide by reflux at 120 °Cfor 3 h with 2-methoxyethanol. The appropriate adjustment of thespinnable sol was achieved by the addition of acetic acid to suppress thehydrolysis reaction and by curing the sol at 80 °C to promotethe condensation of the sol. Green fibers with diameters of about 300µm weresuccessfully extruded from the mixture of PZT powder and sol (powder:sol = 5– 8:1,molar ratio). The extruded fibers, sintered at 1200 °C,had a microstructure with 2– 6µmgrains and had no pores or cracks. From the results of displacement behaviormeasurements, the PZT fibers fabricated by firing at 1200 °Cin this study were considered to have the desired piezoelectric properties.

605 Fabrication of Piezoelectric Ceramic Fibers with Pt Core and Evaluation of Their Piezoelectricity

This study aims to fabricate [Pb(Nb_<2/3>Ni_<1/3>)O_3]_<0.55>-[Pb(Zr_<0.3>Ti_<0.7>)O_3]_<0.45>(PNN-PZT) piezoelectric ceramic fibers which has Pt core by extrusion. Since the Pt core can be used as an electrode, piezoelectric ceramic fibers with core can be used as actuators or sensors with the other electrode coated on the outer surface of fiber. In this paper, the process to fabricate PNN-PZT piezoelectric ceramic fibers with Pt core is explained. The fine PNN-PZT fibers with Pt core are fabricated by extrusion of the mixture of ceramic powder and an organic binder with some addictives. Green fibers with a diameter of about 300μm were successfully extruded from the mixture of PNN-PZT powder and each admixture. The extruded fibers sintered at 1200℃ have the microstructure with 2-6μm grains but no cracks. The result of displacement measurement at the center of its cross-section shows that a PNN-PZT fiber with Pt core sintered at 1200℃ in this study has desired piezoelectric properties.

Smart piezoelectric Fibre composites

Piezoelectric materials are capable of actuation and sensing and have found uses in applications including ultrasonic transducers, hydrophones, micropositioning devices, accelerometers, and structural actuators. A composite configuration for structural actuation having significant advantages over conventional piezoelectric actuators has been conceived, and the recent development of piezoelectric ceramic fibres < 100 μ m in diameter has enabled this concept to be realised. It is envisaged that these composites will find uses in contour control, non-destructive testing, vibration suppression, and noise control. The possibility of computer control using closed loop systems has led to these composites emerging as potential 'smart' materials and structures. Since their conception, less than a decade ago, significant advances have been made in many areas concerned with composite performance, such as fibre and matrix technology and configuration optimisation. These advances are charted, the fibre, matrix, and electrode technologies are reviewed, and the manufacture, modelling, and applications of these new piezoelectric composites, known as active fibre composites, are discussed.

Wavelength-tunable add/drop multiplexer for dense wavelength division multiplexing using long-period gratings and fiber stretchers

We have designed and configured a novel wavelength-tunable add/drop multiplexer (ADM) device that employs long-period gratings (LPGs) and piezoelectric ceramic fiber stretchers. The modeling for this ADM predicts that 50 International Telecommunication Union (ITU) dense wavelength division multiplexing (DWDM) channel signals could be selected in the wavelength range from 1526.25 to 1563.75 nm with 0.75-nm channel spacing, which covers the whole C-band gain spectrum of erbium-doped fiber amplifiers. The cross-talk between channels is less then −39 dB, and the total insertion loss of the device is about 0.24 dB which includes the splicing losses, the mode mismatching loss, and the expected losses in the two side-by-side coupled fibers. The tuning of add/drop channels within a limited region can be provided by changing the voltage, which is applied to the piezoelectric ceramic fiber stretchers. This technique is suitable for the in-line implementation of optical communication networks.

217 白金コアを入れた圧電セラミックファイバーの作製

217 白金コアを入れた圧電セラミックファイバーの作製

Finite element modelling of passive damping with resistively shunted piezocomposites

This work aims at modelling passive damping in structures made of composites with embedded resistively shunted piezoelectric ceramic fibres. To this end, a 3D material model is implemented in the finite element (FE) code ABAQUS. Academical test cases as well as a structural case study are presented.

Development of fine scale and large area piezoelectric ceramic fiber / polymer composites for transducer applications

Abstract The development of both fine scale and large area piezoelectric ceramic fiber/polymer composites using the replication technique is reported. These composites are produced using carbon fibers in various arrangements, soaked in a PZT precursor solution, dried and fired to achieve a ceramic relic with the same structure. Relics are embedded in an epoxy matrix, polished, electroded and poled, after which the electromechanical properties are evaluated. Relic processing offers a capability of synthesizing unique structures important for various transducer applications.

Obtention and characterization of piezoelectric ceramic fibers of the system TiO2-PbO-CaO

Abstract It has been developed a procedure to obtain extruded ceramic fibers of Ca-modified PbTiO3. The plasticity needed for the extrusion molding was provided to the crystalline precursor by an inorganic colloid of similar composition which was processed by a sol-gel method. Due to the presence of the gel phase, the acuous mixture of both components presents a high reactivity which enhances the sintering mechanisms and gives place to a particular microstructure of the sintered fibers that relates to its electromechanical properties.