| With the development of natural science, piezoelectricity has been one of the important subjects in the modern science and technology. The research on the new materials and technologies has been one of the advances in sciences. PMS-PZT piezoelectric ceramic has been widely used in the field of electrics-information and aerospace industry. The ceramic is used to convert the electric energy and mechanical energy through the piezoelectric effect. It has the especially significant status in the field of inorganic functional material.As a crucial step of fabrication of PMS-PZT ceramics, compression molding plays an important role in the sintering and performances of products. It is one of the most simple and intuitive powder molding process and widely used in industrial production. It is the priority program to optimize the experiment of compression molding. Recent studies have shown that this method can be used to press the piezoelectric ceramics efficiently whose thickness are less than 60 mm. However, the samples can produce some phenomenon on the microscopic structure such as uneven density and different stress, which can produce adverse effects on the electrical and physics properties. In this paper, the two-steps sintering process is used to prepare three kinds of PMS-PZT ceramic’ samples based on the technology of compression molding. The reasons of failure modes such as shape shifting, fracture and melt are analyzed in the experimental process. Meanwhile, based on the analysis of the microscopic structure and failures, the volume density and some parameters of the samples are measured and calculated.In the compression molding, it is difficult to obtain the exact solution of stress and density distribution on the microscopic structure only by the experiment, because of the complex boundary conditions such as the contact between the powder and the die. In this paper, the PMS-PZT powder is assumed to continuous medium which can be pressed by the external force. The finite element model for the compression molding of PMS-PZT powder is been established based on the large deformation elastic-plastic theory. In the process, the ANSYS software is been used to calculate this model. The stress distribution and mobility of particles are analyzed while the maximum external force is 70 Mpa and the coefficient of friction between the powder and the die is 0.2 based on the Drucker-Prager model. Meanwhile, the different stress distributions are analyzed and compared on the different coefficients. It shows the friction is the important factor for the internal structure. The finite element results are consistent with the experiment data.Finally, in order to measure the piezoelectric effect of the samples, the piezoelectric ceramic bimorph element model is been established based on the electromechanical coupling theory. The material parameters of the model are measured by PMS-PZT samples in the above. Then, the drive and response characteristics of this model are simulated. It shows the deflection of the free-end is directly proportional to the voltage. The results based on the finite element simulation agree on the theoretical data.In this paper, the finite element simulation and the experiments are combined to study the compression molding of PMS-PZT piezoelectric ceramic and the drive and response characteristics preferably. The study provides a new and effective method to optimize the preparation technology of piezoelectric ceramics. The research shows that the method of combing can be used to guide the study of piezoelectric ceramics effectively and can reduce the workloads of experiment and produce development cycle. And the cost of the produce development can be reduced. |
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