Investigation On The Double-scale Expression Method Of Lattice Component Based On Half-face Structure/Wire-frame Structure

Lattice material component is a kind of multi-functional lightweight material part that integrates high specific strength,high specific stiffness,energy storage,energy absorption,stealth,damping and thermal control.And its open and continuous space inside provides the conditions for the burial of multi-function devices,so it has been widely used in many fields such as spacecraft,aircraft,ships,medicine,sports,transportation,construction,energy and so on.In order to better apply lattice material components to various engineering fields,meet the design requirements of specific engineering problems,and solve the problems existing in the representation of part information expression in lattice material components design and additive manufacturing,on the basis of the previous CAD modeling expression methods of heterogeneous material components,this paper regards lattice as a kind of material with macroequivalent material properties based on the homogenization theory.The CAD model of lattice material components is expressed from two levels of macro and meso,and the macro-meso representation is connected through the database to establish a double-scale CAD model of lattice material components.The main research work of this article is as follows:First of all,the current problems in the expression of component information in the design and manufacture of lattice material components,the development of CAD model technology and the expression method of CAD models of heterogeneous materials are reviewed in the introduction.So we clarify the problems to be solved by this topic and their research significance.Secondly,aiming at a series of problems in the design and manufacture of lattice material components,such as the loss of design intent,breaking through the boundary between traditional materials and structures,the lattice is regarded as a designable material with macroequivalent material properties based on the homogenization theory.Therefore,the lattice material components composed of a single material and complex structure are converted into equivalent material components composed of multiple materials and relatively simple structure.And based on the boundary of equivalent material properties appearing inside,a double-scale CAD model combining macro and meso representations is proposed.Then,according to the non-manifold characteristics existing on the macro-scale of the lattice material components,comprehensively considering the applicability and simplicity of various non-manifold expression methods,this article chooses to use a half-face data structure to organize its geometric / topological information and equivalent material attribute information,give a specific data structure,verify the rationality and feasibility of the data structure through an example of macro-equivalent material attributes,and establish a complete macro-scale CAD model.Finally,the geometric / topological information and material information on the mesoscale of the lattice material components are described in detail,and the data structure describing the lattice mesoscopic geometry / topology information and material information is given.And through the pyramid lattice structure to verify the rationality and feasibility of the data structure,a complete meso-scale CAD model is established.Through the database,the macro and meso CAD models of the lattice material components are connected to establish a complete doublescale CAD model of the lattice material.