Weight Reduction Design Of SIMP Struc-tural Topology Optimization For Additively Manufactured Gooseneck Chains Based On Static Strength

With the widespread use of structural topology optimization techniques in finite element analysis software and the rapid development of additive manufacturing technology,the freedom of structural design has been greatly freed up,offering greater possibilities for lightweight design of structures.However,inaccurate finite element models in structural topology optimization can reduce the reliability of the optimization results,and unreasonable parameter settings can lead to structural topology optimization results with features such as isolated bodies and broken branches that affect structural performance.How to improve the manufacturability of structural topology optimization results and maximize the advantages of combining structural topology optimization and additive manufacturing technologies is an important issue in practical engineering applications.This paper takes a typical metal sub-load-bearing civil aircraft component gooseneck chain as the research object,and starts a systematic research around the structural topology optimization design of additive manufactured parts based on static strength,mainly including the following parts:（1）Design and implementation of static verification scheme for gooseneck chain finite element model of additive manufacturing.For the additive manufacturing gooseneck chain provided by a company,a supporting fixture was designed,static tests and reliability evaluation of test data were conducted,and the error between the finite element analysis results and the average value of test data for different titanium alloy material properties was analyzed by taking the average value of test data as the benchmark,verifying the accuracy and reliability of the finite element model,and providing a test-proven and more accurate finite element model for the subsequent structural topology optimization in the finite element.（2）Analysis of the influencing factors of structural topology optimization.Through the secondary development of the commercial software Abaqus,a study on the influencing factors of structural topology optimization was conducted with the original gooseneck chain as the object,and the influence of each influencing factor of mesh type,mesh size,material properties,initial density,filter radius and penalty factor on the structural configuration of structural topology optimization was explored,and the recommended criteria for each influencing factor were proposed.The proposed recommended criteria improve the manufacturability of structural topology optimization.（3）Study of geometric reconfiguration of structural topology optimization results based on selective laser melting.In response to features affecting structural performance such as isolated bodies and broken branches that occur in structural configurations of structural topology optimization and the manufacturing constraints of selective laser melting techniques.The geometric reconstruction criteria in the post-processing process of structural topology optimization are proposed,the methods for achieving geometric reconstruction were analyzed in depth,and the geometric reconstruction route was formulated.Finite element analysis of the geometric reconstruction model was carried out with the help of orthogonal tests,and the weights of each factor of mesh size,filter radius,penalty factor on flexibility,maximum stress,weight reduction ratio and calculation time indexes were determined by means of extreme difference and variance analysis.The optimum geometric reconstruction models for the hexahedral and tetrahedral mesh configurations were determined using the integrated equilibrium method,with weight reductions of 23.46%and 22.22% respectively compared to the original model and 4.08% and 2.84% respectively compared to the model provided by a company,and the maximum stresses were reduced to 948.8MPa and 998.5MPa respectively,meeting the requirements of the static working conditions.