| Advanced ceramics can bear the rigorous working environment that metal and macromolecule materials would not be competent in due to their high heat-resistant, high wearable, high corrosive-resistant and high hardness. Therefore, they become the physical foundation of modern high-tech. However, there are gross dimension deviations of these ceramic components executed by the sintering circuit which resulted from the shrinkage in the drying and sintering process. Due to the difficulty of dimension control, these ceramic components could not be used in engineering field at first hand especially to those components which had complicated figures. Consequently, further machining processes are needed on these advanced ceramic components after the sintering process in most cases. To a great extent, the extensive use of advanced ceramic material as a structural engineering material lies on the development of the processing methods especially the finishing machining technology. The traditional methods of machining these materials using diamond grinding are very slow and expensive. Recently, WEDM(wire electrical discharge machining) as an economical and practical processing method to these materials began to be paid great attention to.So far, the research about machining advanced ceramics by WEDM limits only in vertical plane machining. Although WEDG(wire electro-discharge grinding) can be used for machining axisymmetric shapes, it is very expensive too and now just restricted to micro-shaft machining. For those slender axisymmetric ceramic products, when we use WEDM coupled with a rotating workpiece system, the resistance between the clamping position and discharging point is different from place to place along with the automatic feed of working table. Then it makes a direct result that is the continuing changes in discharge parameters and eventually it will make the surface roughness of those ceramic products uneven, the process is unstable as well.Base on the WEDM machine and the rotating workpiece system, a tracking electrode device had been carried out to make the surface roughness more homogeneous and the process more stable in the WEDM of the axisymmetric shapes of large resistivity ceramic materials in this paper. The tracking electrode device thus could improve the process of WEDM of axisymmetric shapes of large resistivity ceramic materials. The selected material in this paper is hot-pressed Al 2 O3? TiC composite ceramic with 30% TiC (the volume fraction is 25.8%; the Rockwell hardness, 94HRA; bending strength, 800-1100Mpa; electrical conductivity, about 20Ω?cm). Accordingly, simulation analysis and related experiments had been carried out for the development and the performance verification of the tracking electrode device. The main contents of the research are as follows:A thermal model of single spark during WEDM axisymmetric shapes of Al 2 O3? TiC ceramic was developed based on the heat conduction theory and finite element method. This model had considered the impact of the TiC added phase, porosity as well as latent heat on the heat physical parameters of this material. Important parameters such as energy partition to the workpiece, spark radius and convective heat transfer coefficient were determined too. A Gaussian heat flux distribution was assumed in the model to simulate the heat flux due to a single spark. The element type Quad 4node 55 was chosen as the thermal analysis element to mesh the model. A comparative analysis had been carried out to estimate the temperature field in the workpiece due to different discharge energy. The general relationship between the discharge energy and the discharge erosion had been concluded. The comparative analysis showed that the change of discharge energy would have a very big influence to the whole process, especially to the surface roughness and the material removal rate.Owing to the big influence to the whole WEDM process caused by the change of discharge energy, a tracking electrode device had been carried out to make the discharge energy more stable in the whole WEDM process of the axisymmetric shapes of large resistivity ceramic materials. The tracking electrode device must maintain a certain distance to the electrode wire. Also, it must always keep close contact with the workpiece to make sure the continuous conduction of the WEDM process system. It must have the ability to adapt the arbitrary shape of the workpiece automatically to meet the need of machining arbitrary shape on the workpiece. A simulation of kinematic and dynamic characteristics had been carried out to the design of the tracking electrode device with the help of CATIA, ADAMS and ANSYS. First, the component models of the tracking electrode device had been established in CATIA. And then, through the interface documentation STEP, the transformation from CATIA model into ADAMS format had been done. The restraints and loads had been imposed on the assembled model in the ADAMS environment. The dynamic simulation had been carried out in the ADAMS environment and the important data such as the contact between the tracking electrode device and the workpiece, the spring force and the response curve of the spring force and the device position had been obtained through simulation. According to the load data obtained in ADAMS, a finite element model had been established using the newly ANSYS Workbench. Through modal analysis of structural dynamics, ANSYS obtained the inherent characteristics of the tracking electrode device, the first ten natural frequencies of vibration and corresponding modes was obtained as well. It was observed that there would not be resonance under the excitation frequency. Through harmonic response analysis, the response of the model under the excitation frequency had been calculated, thereby improved the structural design of the device to make sure that the device could still keep close contact with the workpiece even though under the excitation frequency.According to the result of the kinematic and dynamic simulation, the tracking electrode device was made and a comparative study had been carried out on the influence of the tracking electrode device over surface roughness (evaluated through the Ra parameter) of WEDM of ceramic. The experimental results showed that the differences of the surface roughness between the near-clamping position and the away-clamping position without installed the tracking electrode device were 25%-30%, as the differences were only 5% with the tracking electrode device. The experimental results proved that the surface roughness was more Al 2 O3?TiChomogeneous and the processes were more stable with the help of tracking electrode device. The device can benefit the whole WEDM process of the rotating surface of advanced ceramics indeed.A tracking electrode device was introduced into the research of WEDM of rotating surface of large resistivity ceramic materials such as ceramic in this paper. After the simulation and experiments to the tracking electrode device, it was proved that the device can benefit the whole WEDM process of the rotating surface of advanced ceramics with large resistivity, especially to the surface roughness and the material removal rate. The tracking electrode device is a effective device to the WEDM process of the rotating surface of advanced ceramics with large resistivity and the idea that track the electrode wire to make the discharge parameters stable may have significance to other correlative researches. Al 2 O3?TiC...
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