A Low-voltage Graphene/Ag-based Electrothermal Phase Transition Actuator

With the development of actuators,electrothermal phase transition actuators have been concerned by researchers due to their good deformation characteristics and flexibility.The phase transition actuator can produce excellent compatibility with the environment and have a good application prospect in soft operating equipment,bionic equipment and medical treatment.In this paper,choosing silicone rubber as the base material,high electric resistance,thermal conductivity and electron mobility of graphene(GR)and high conductivity thermal conductivity and large specific surface area of Nano silver(Ag)as composite electrothermal material.Research the influence of the mass ratio between GR and Ag,and the total mass fraction on the mechanical and electrical properties of the electrothermal film.An electrothermal substrate with a mass ratio of 1:4.5 between GR and Ag,and total mass fraction is 60%of the electrothermal material was prepared.Ethanol solution was selected as the phase transition material and latex film as the deformation layer,and then designs the low-voltage electrothermal phase transition actuator.The operation state of the actuator can be controlled by applying a wave signal with amplitude of 6 V,frequency of 1 Hz and duty cycle is adjustable.The gripper,auto-injector and bionic swim bladder were prepared based on the electrothermal phase transition actuator.The gripper can hold objects with different masses and thicknesses stably.The auto-injector can control the liquid output by adjusting the working cycle.The internal air pressure of the bionic swim bladder can be adjusted by the phase transition actuator to control the upward and downward movement of the bionic fish.The results show that the electrothermal phase transition actuator has the advantages of simple preparation method,easy operation,light weight(1.4g),low driving voltage and the state can be controlled.The maximum external force can be up to 1N,and the minimum control accuracy is 0.02N.Due to its good flexibility,controllability and large deformation,it is expected to be widely used in soft robots,bionic devices and medical treatment.