The effects of materials on the performance of the cymbal-type flextensional transducers were investigated under in-air and water-loaded conditions by finite element analysis (FEA) methods. At the initial stage, FEA and experimental studies were conducted in parallel to gain experience with the FEA models. Later, all calculations were carried out by computational methods: resonance frequencies, projector TVR, receiver FFVS, effective coupling coefficient (k eff ), and mechanical quality factor (Q m ) were calculated. Ceramic and endcap materials have strong effects on the TVR/FFVS performance of cymbal transducers. It is possible to tailor a wide range of flexural resonance frequencies by optimizing the ceramics used as the driver and the metals used as the endcaps.

Absfracf-Cymbal transducers are small, thin Class V flextensional transducers. A single cymbal element consists of a piezoelectric disk sandwiched between two metal cymbal-shaped endcaps which serve as mechanical translormers, converting the low impedance, small extensional motion 01 the ceramic into high impedance, large flextensional motion 01 the endcap. A cymbal transducer element is very small, with a thin profile. A single element is characterized by high Q, low elficiency, and medium power capability. When comparing cymbals to other transducers, the designer should consider their use in large flexible, Iov cost arrays.This paper represents the work 01 eight researchers over a period 01 several years. The ellects 01 changes in materials and dimensions on the cymbal-type flextensional transducers, in-air and water-loaded, were examined experimentally and through finite-element-analysis (EEA).Experimental and FEA calculated results matched quite well. After gaining experience and confidence in the FEA models, extensive parametric studies were performed using FE.4 to investigate the size and material effects on cymbal transducer characteristics. The scaling lactor (i.e., overall size), endcap stiflness, and cavity design have the strongest influence on resonance frequency. Adjusting the dimensions and materials used lor drivers and endcaps provides a range in the fundamental flexural lrequency lrom aboul 5 to 150 kHz in water. These results also indicate trends that can be used to extend the ranges lurther. The sealing factor, cavity depth, and PZT thickness had the strongest ellects on the projectorlreceiver perlormance (TYWFFVS). Investigations are underway lo combine and optimize some of these parameters lor potentially significant improvements in bandwidth and efficiency.

In this study, metal cation consisting calcium phosphate based antibacterial ceramic powders were synthesized with wet chemical technique. The developed antibacterial powder was added to the glaze composition of the ceramic sanitary and tiles wares. Antibacterial test were performed to investigate the bactericide power of glazed surface against harmful pathogenic microorganisms. For the antibacterial test E-coli bacteria were used, because it is the mostly encountered bacteria type for human beings in daily life.

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