• CN:11-2187/TH
  • ISSN:0577-6686

机械工程学报 ›› 2018, Vol. 54 ›› Issue (5): 156-165.doi: 10.3901/JME.2018.05.156

• 数字化设计与制造 • 上一篇    下一篇

扫码分享

SLM制备的Ti6Al4V轻质点阵结构多目标结构优化设计研究

柏龙, 熊飞, 陈晓红, 易长炎, 张俊芳, 陈锐   

  1. 重庆大学机械传动国家重点实验室 重庆 400044
  • 收稿日期:2017-02-13 修回日期:2017-11-28 出版日期:2018-03-05 发布日期:2018-03-05
  • 通讯作者: 柏龙(通信作者),男,1982年出生,博士,副教授,硕士研究生导师。主要研究方向为仿生机构、特种机器人、高性能轻量化材料与结构一体化设计。E-mail:bailong@cqu.edu.cn
  • 基金资助:
    国家自然科学基金(51405046,51505044)和重庆市基础科学与前沿技术(cstc2016jcyjA0472)资助项目。

Multi-objective Structural Optimization Design of Ti6Al4V Lattice Structure Formed by SLM

BAI Long, XIONG Fei, CHEN Xiaohong, YI Changyan, ZHANG Junfang, CHEN Rui   

  1. State Key Laboratory of Mechanical Transmission, Chongqing University, Chongqing 400044
  • Received:2017-02-13 Revised:2017-11-28 Online:2018-03-05 Published:2018-03-05

摘要: 体心立方(Body-centered cubic,BCC)点阵结构作为目前被广泛关注的点阵材料构型,其拓扑类型简单、SLM(Selective laser melting,SLM)成型可靠性好、压缩失效形式单一,但存在着承载能力相对较差的缺点。为探寻兼具轻质与高强性能的点阵构型,首先解除BCC点阵单胞各向尺寸相同的约束,提出体心四方(Body-centered tetragonal,BCT)点阵结构一般模型。然后,以BCT单胞构型尺寸为设计变量,以点阵材料尺寸与成型工艺为约束条件,以相对密度、初始刚度、塑性破坏强度为多目标评价函数,建立BCT点阵结构构型尺寸的多目标优化数学模型,采用理想点法求解得到BCT点阵单胞综合最优构型尺寸,并与BCC参照结构进行实例仿真对比分析,论证BCT优化结构相比BCC参照结构在性能上的优势。最后,采用Ti6Al4V材料通过SLM方法制备BCT优化结构与BCC参照结构的实验样件,并进行准静态单向压缩性能实验,验证理论分析结果的正确性,为轻质点阵结构材料的设计与研究提供了理论参考。

关键词: BCC点阵, BCT点阵, SLM, 点阵结构, 多孔材料

Abstract: Taking advantages of simple type of topology, high manufacturing reliability and single form of compression failure, body-centered cubic (BCC) lattice structure has raised a widespread concern in recent years. However, it has the shortcoming of relatively poor bearing capacity. In order to explore a specific kind of lattice structure with light-weight and good mechanical properties, a body-centered tetragonal (BCT) lattice structure is proposed by removing the constraint of isotropy size in BCC lattice structure. A multi-objective optimization model for the configurational size of the BCT lattice structure is developed by taking the size of BCT cell configuration as the design variables, the size of lattice material and manufacturing process as the constraints, and the relative density, the initial stiffness and the strength of plastic collapse as the multi-objective evaluation functions. Based on the optimization model, the optimal configuration dimension of BCT lattice cell is obtained by using the ideal point method. The performance advantages of the optimized BCT structure are proved by comparing with the BCC reference structure through simulation analysis. Finally, the experimental samples of the optimized BCT structure and BCC reference structure are fabricated by selective laser melting (SLM) using the material of Ti6Al4V. The quasi-static uniaxial compression experiment is conducted and the theoretical analysis results are verified. The theoretical and experimental results have general applicability to the design and research of the light-weight lattice structure materials.

Key words: BCC lattice, BCT lattice, cellular material, lattice structure, selective laser melting

中图分类号: