轻质点阵超结构设计及多功能力学性能调控方法

随着先进制造技术、多学科交叉和人工智能科技的飞速发展,高端装备呈现出轻量化、集成化、复合化、功能化、智能化、柔性化和仿生化等发展趋势.传统结构研究存在结构设计和制造相互分离,复杂结构制造效率低、实际制造结构的性能指标和使用可靠性大幅低于设计理论预测、结构多功能一体化程度不足、经济成本过高等问题.此外,先进工业装备对材料、结构的使用性能、使用环境要求越来越高,亟需开展结构的设计、制造、功能、应用一体化研究,为解决我国先进制造“卡脖子”技术难题提供理论依据和技术支持.轻量化多功能点阵超结构具有轻质高强、抗冲击吸能、减振降噪等性能优势,在航空航天、交通运输、国防、生物医疗、能源、机械等工业领域具有巨大的应用潜力.有鉴于此,受多晶体微结构的多尺度力学设计启发,以“点阵超结构力学设计”为主题,开展点阵超结构的节点、杆件组元,胞元类型、双相结构、梯度结构、多层级结构等典型点阵超结构的几何构筑和力学设计,并阐明多晶体多尺度微观结构启发的点阵超结构力学设计基本原理、多功能力学性能调控方法,以及点阵超结构在不同类型载荷下的结构变形和失效物理机理.

Design of lightweight lattice meta-structures and approaches to manipulate their multi-functional mechanical properties

With the rapid development of advanced manufacturing technology, multidisciplinary integration, and artificial intelligence technology, high-end equipment demonstrates the development trends of lightweight, integrated, composited, multi-functional, intelligent, flexible, and biomimetic features. Traditional structural research has encountered many intrinsic problems that constrain devices, and instruments performances, such as structural design and manufacturing are separated from each other, relative low manufacturing efficiency of complex structures, practical structural performances, and reliability of manufactured structures are significantly lower than theoretical predictions, insufficient multi-functional integration of structures, and high costs. In addition, materials and structures for constructing advanced industrial equipments are required to maintain reliable performances and endure extremely crucial service environments. It is urgent to carry out research on the synergy effects of design, manufacture, function, and applications of structures, thus providing theoretical foundations and technical support for solving the key technical problems of advanced manufacturing strategic plans. Lightweight multi-functional lattice meta-structures exhibit extraordinary mechanical performance advantages of lightweight, specific strength, impact energy absorption, shock absorption, and noise reduction advantages, and demonstrate great industrial application potentials in aerospace, transportation, national defense, biomedical, energy, machinery, equipment, and other industrial fields. Considering the above-mentioned status-quo, inspired by the multi-scale microstructures of the polycrystalline, the mechanical design of lightweight multi-functional lattice meta-structures is reviewed in this paper, and is elaborated from the perspectives of typical design methods, such as nodes, strut components, unit cell types, dual-phase structures, gradient structures and hierarchical structures of lattice structures. Afterward, physical foundations for design innovations based on multi-scale microstructures of polycrystalline are explained, rational regulations of multi-functional mechanical properties, and the underlying deformation and failure mechanisms are demonstrated.