Study On The Mechanscs And Electrical Coupling Behavior And Its Application Of Liquid Metal Embedded Elastomers

As a typical electroactive soft material,dielectric elastomers(DEs)have the advantages of "small excitation,large deformation",fast response speed,light weight,low cost and so on.They show great potential in the new fields of flexible actuating,sensing and so on.In this paper,the main research object is the dielectric elastomer material.Firstly,the basic theory of the dielectric elastomer in the coupled field is summarized,and the free energy model is described.Then,the finite element modeling and calculation of the dielectric elastomer are introduced,and ANSYS finite element is used to calculate the dielectric elastomer actuator,which paves the way for the subsequent work.In the further study,the influence of material thickness and pre-stretch on the breakdown field strength of dielectric elastomer is explored.The empirical relationship between the breakdown field strength and thickness and pretension of PDMS dms-v35 is given.The theoretical analysis results are in good agreement with the experimental test results;The main failure modes and energy conversion mechanism in the process of dielectric elastic physical electric coupling are described.The main failure modes and energy conversion mechanism in the process of the electro-mechanical coupling of the dielectric elastomer are described.Using the Gent strain energy model,four failure modes are considered under the equal biaxial deformation mode,the allowable area and the maximum energy collected by the system are discussed.High driving voltage has always been one of the obstacles to the development and application of dielectric elastomer materials,so how to prepare dielectric elastomer materials with high permittivity and low driving voltage is the current research hotspot.By doping liquid metal Galinstan into Ecoflex matrix,which is called liquid metal embedded elastomers(LMEEs),this kind of material has high dielectric constant and low elastic modulus.Compared with traditional Ecoflex,its dielectric constant increased by 110%to 13,while its elastic modulus only increased slightly.Then,through the experiment,we focus on the study of the voltage-induced deformation based on the LMEEs circular actuator.The experiment shows that when the mass ratio of liquid metal Galinstan/Ecoflex silicone rubber take the maximum value 3:1,the maximum area strain is obtained,which up to 92%,which verifies the feasibility of LMEEs as a flexible actuator material,and the driving voltage is significantly reduced after doping the liquid metal.In addition,the experimental study of LMEEs as a flexible strain sensor is carried out.The experimental results show that the linearity of the material as a sensor is good and the measurement accuracy is high.This work provides a theoretical basis for LMEEs as a flexible transducer material and an important guidance for the actual device design.