Research On Molding Equipment And Process Of Silicone Material With Programmable Hardness Control

The design and preparation of intelligent soft materials is the key technology supporting cutting-edge disciplines such as soft robots,flexible sensing,and bionic design.Silicone material is one of the most used smart soft materials.It has the advantages of high elasticity,fast response speed,wide applicable temperature,high dielectric elasticity,and good biocompatibility.It is necessary to study its design and preparation technology.The existing soft structures made of silicone materials are mostly made of homogeneous materials,and their performance is isotropic.The deformation control of each part can only be achieved through the design of the structure size,which often makes the structure bloated,and the response is slow.The integrated design prepares hardness programmable soft materials with different hardness properties in different parts to meet the specific deformation requirements of each part,which can add a new dimension to the design of intelligent software structures.Based on the basic principle of additive manufacturing,this topic explores the preparation technology of hardness programmable soft materials from three aspects:equipment construction,numerical simulation,and experimental preparation,and characterizes its products.The main research contents and conclusions are as follows:(1)A variety of silicone rubber extrusion preparation methods were compared and tested,the three-dimensional motion platform structure was determined,the dual-channel direct ink writing method was established,the dual-channel silicone rubber printing device with controllable hardness was built,and the printability was evaluated;(2)Taking the silicone rubber as an example,the influence of additive content on the printing.accuracy of different material products was explored.The silicone rubber material which is most suitable for direct ink writing was obtained through experimental comparison.Through orthogonal experiments,the influence of layer height,extrusion speed,and printing speed on the printing of liquid silicone was further studied,and the best printing process parameters of liquid silicone were obtained;(3)Through the flow simulation of extrusion in the dual-channel direct ink writing process,the mixing effect of different total flow rates and different flow rate ratios on the mixing effect of soft and hard materials at the nozzle outlet,and the speed and direction of material extrusion are explored,which provides a theoretical basis and reference for the dual-channel direct ink writing experiment;(4)Through experiments,the optimal process parameters of dual-channel silicone rubber direct ink writing were explored,and the mixing effect of the device was verified.Multiple products with multiple hardness and a single product with multiple hardness were prepared.The relationship between the dual-channel extrusion flow rate and the hardness,tensile properties of the product is obtained,which opens up a new direction for subsequent further research.