Geometric Deformation Compensation For Micro-stereolithography Of Piezoceramic

Piezoceramic is brittle and difficult to be processed,so it is hard to make piezoceramic devices with complex structures.In additive manufacturing technology,micro-stereolithography has the highest molding accuracy.By curing ceramic slurry containing photosensitizer layer by layer,3D entities with arbitrary structures can be quickly printed,which meets the requirements of micro-piezoceramic devices.However,piezoceramic devices based on micro-stereolithography still have some problems,such as low density,low performance and poor geometric accuracy.In order to improve the dimensional precision of piezoceramic,a Bayesian statistical modeling and reverse design methods were used to predict and compensate the deformation of piezoceramic.Take into account the small size of the prepared piezoceramic elements and the difficulty in measuring 3D deformation,a 3D scanner was used to obtain the outer contour of the printed parts.Combined with MATLAB programming,the deformation of piezoceramic elements can be quickly measured and feedback.To conclude,the main contributions of this dissertation are as follows:1.The deformation mechanism of piezoceramic in the process of photo-curing,degreasing and sintering was analyzed.The piezoceramic with high compactness and complex shapes were prepared,through material components design,precise control of photo-curing and heat treatment parameters.The results show that the relative density after sintering can reach 96% when the mass fraction of piezoceramic(PZT-5H)slurry is 75%.2.Based on the statistical data of deformation in the preparation process and combining with the deformation mechanism,the mathematical prediction and compensation model of deformation were established.In particular,a new cookie-cutter function was proposed to solve the problem of "roundness" for prismatic ceramics.3.According to the deformation model,a compensation experiment was designed for cylindrical and prismatic piezoceramic elements.Rapid feedback and deformation compensation of ceramic in the whole preparation process could be realized by reverse modeling.The results show that the dimensional accuracy of piezoceramic can be improved by 80% after compensation.