| Triply periodic minimal surfaces is a very simple and complex structure with mathematical expressions.It constructs a three-dimensional space periodically(along with periodic changes along the X,Y,and Z axes).A smooth,fully connected porous structure.TPMS is a minimal surface with periodicity in three independent directions in threedimensional space.TPMS is widely used in aerospace and automotive fields,and its main purpose is to carry out lightweight design.There are two ways to describe the minimal surface in mathematics,which are to describe it from the perspective of area and curvature.From the perspective of area,the minimum surface refers to the surface with the smallest area under all external constraints(the constraint condition can be the perimeter information of the surface,some external stress conditions,etc.),so from the area It can be seen that the minimal surface has excellent physical properties;to describe it from the perspective of curvature,the minimal surface refers to a surface with an average curvature of 0.However,the performance of TPMS structure is closely related to the preparation method,and the quality of the structure directly determines the quality of the preparation method.As one of the 3D printing technologies,DLP(digital lighting processing)technology has the unique advantages of high flexibility and applicability,low cost,and computer control in the molding method.Therefore,it is expected to become a new and efficient method for preparation.In this paper,for the first time,a ceramic TPMS structure with excellent properties was prepared using DLP technology.At the same time,the influence of printing parameters on the curing effect was studied.The mechanical properties of different TPMS structures were studied using quasi-static compression experiments.Impact on performance.The main content and results are as follows: 1.The effects of different exposure times and printing angles on the three-point flexural strength of the prepared samples were studied.The effects of exposure time and printing angles on the three-point flexural strength of the samples were studied by the soft start method.When the weak exposure time is 1 s and the strong exposure time is 13 s,the average strength of the three-point bending strength of the test strip can reach 580 MPa.In addition,the sample printed at 45° has the lowest intensity when rotated along the x-axis,and the printed strength at 0° The sample strength was the highest.2.The mechanical properties of four TPMS structures are studied: the mechanical properties of p-cell,gyroid,IWP,s14,respectively.The results show that the compressive strength of the TPMS structure increases with the increase of relative density.IWP and s14 structures show similar mechanical responses under stress.In general,all TPMS structures have> 2% strain capacity,and the compressive strength is> IWP> gyroid> p-cell in the order of s14.The S14 structure can achieve a high compressive strength of 105 MPa at a structural density of 30.47%,while the gyroid structure can achieve a compressive strength of 5.56 MPa at a very low structural density of 6.71%.Ceramic TPMS structure obeys(Pabst-Gregorova)index prediction.3.The effect of changing the stacking mode of TPMS structure unit cells on the mechanical properties of the structure under the condition of constant relative density is studied.The results show that the compressive strength increases with the increase of the x-y plane,and the compressive strength increases with z.As the axis increases,it decreases.p-cell always shows the worst compressive strength,IWP,neovius,diamond show similar mechanical behavior... |
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