Research On Controllable Porous Structure Based On TPMS

With the widespread application of porous structures and the rapid development of 3D printing technology,the direct manufacturing of porous implant parts becomes possible.Due to the huge difference in elastic modulus between the implant and the bone,the stress cannot be fully removed from the implant.The body is directly transferred to the bone tissue.Therefore,the design and manufacture of a porous structure that meets the requirements in terms of structure and mechanical properties has become an urgent problem to be solved.For this reason,based on the TPMS(triply periodic minimal surface)model,a modeling method of controllable porous structure is proposed,and the influence of controllable parameters on the pore size and porosity is discussed,and the effects of the controllable parameters on the pore size and porosity are studied.The influence of pore size and porosity on strength and equivalent elastic modulus.The specific research work is as follows:1.Propose a modeling method of controllable porous structure.First,use TPMS to digitally model the controllable porous structure,and construct porous structural units with different shapes and porosities by changing the controllable parameters.Then the corresponding relationship between the porosity,pore size and controllable parameters of the TPMS unit geometry is explored,and the least squares method is used for fitting.It is found that the porosity,pore size and the controllable parameters have an approximately linear relationship.Finally,the Sigmoid function is used to fuse the two TPMS units,and then the controllable porous structure model of the gradient change of the TPMS unit is constructed.2.Preparation and performance study of controllable porous structure.First,light-curing3 D printing equipment is used to prepare porous structure samples with different pore diameters and porosities,and then the compressive strength is tested by a universal testing machine,and finally the porous structure samples are tensile tested using a μTS measuring device.The experimental results show that: different types of porous structures present different fracture forms,and the number of cycles,structure types,and porosity all affect the mechanical properties of the porous structure;the equivalent elastic modulus of the porous structure is mainly related to the controllable parameters.As the control parameter t increases,the equivalent elastic modulus also gradually increases.