Research On The Design And Experiment Of PZT Micropumps Based On PDMS

Piezoelectric driven micro pump is called PZT micropump for short, It used the inverse piezoelectric effect to drive the medium, it is a new type of reciprocating displacement pump and has many advantages, such as small volume, fast response, no electromagnetic interference, the output of high precision, easy to control etc. It is an important executive component in micro mechanical fluid system. After 30 years of research and development, Piezoelectric pump has been widely used in aerospace, medical equipment, experimental analysis, MEMS and other fields. Along with the piezoelectric pump’s application area is wider and wider, it need to adapt to different work environment and transport special fluid, so these put forward higher requirements for the choice of pump body materials.In order to further expand the application fields of PZT micropumps and facilitate them to be better integrated in the microfluidic chip, series of PZT micropumps based on solid Polydimethylsiloxane(PDMS) pump body material are presented in this paper and the relevant experiments has been carried out. This paper describes the piezoelectric effect and inverse piezoelectric effect, analysis of Piezoelectric vibration force model, use the finite element method to do the static analysis and modal analysis for Piezoelectric vibrator,then Calculation of deformation of piezoelectric vibrator and select the appropriate piezoelectric vibrator. Design the structure of PDMS PZT micropumps according to the experiment need. For improving the working performance of PZT micropump to the maximum extent, the rational structure adjustment and design are used, including the adjustment of PZT actuator’s support mode, the optimal design of series and parallel structure of micropumps chambers and valve structure, etc. The mould of pump body is made by carved machine from PMMA plate, and the PDMS pump body is made in the method of resin transfer moulding.In the lab, various types of piezoelectric pump were fabricated respectively using PDMS and PMMA, and the working performances of related prototypes were tested and compared. The test results show that constructing PZT micropump with good working performance based on PDMS is feasible by reasonable structure design. Under voltage 90 V,frequency 80 Hz, the output flow rate of PDMS dual chambers micropump with series structure can reach 21ml/min, output backpressure can reach 10 kPa. However, compared with the PMMA micropumps, the comprehensive performances of PDMS micropumps still have nearly 30% performance gap, but the output ability can meet the needs of microfluidic chip, and PDMS PZT micropump have better performances for transporting high viscosity solution. The related experimental research provides useful reference and technical support for PZT micropump future integration into microfluidic chip.