As one kind of key components with enormous quantities and diversities, the bent tube parts satisfy the increasing needs for lightweight and high-strength product from both materials and structure aspects. The bent tu...As one kind of key components with enormous quantities and diversities, the bent tube parts satisfy the increasing needs for lightweight and high-strength product from both materials and structure aspects. The bent tubes have been widely used in many high-end industries such as aviation, aerospace, shipbuilding, automobile, energy and health care. The tube bending has become one of the key manufacturing technologies for lightweight product forming. Via the analysis of bending characteristics and multiple defects, advances on exploring the common issues in tube bending are summarized regarding wrinkling instability at the intrados, wall thinning （cracking） at the extrados, springback phenomenon, cross-section deformation, forming limit and process/ tooling design/optimization. Some currently developed bending techniques are reviewed in terms of their advantages and limitations. Finally, in view of the urgent requirements of high-performance complex bent tube components with difficult-todeform and lightweight materials in aviation and aerospace fields, the development trends and corresponding challenges are presented for realizing the precise and high-efficiency tube bending deformation.展开更多
Multi-functional Al-matrix composites with high volume fraction （55%-57%） of SiC particles are produced with the new pressureless infiltration fabrication technology. X-ray detection and microscopic observation disp...Multi-functional Al-matrix composites with high volume fraction （55%-57%） of SiC particles are produced with the new pressureless infiltration fabrication technology. X-ray detection and microscopic observation display the composites which are macroscopically homogeneous without porosity. The investigation further reveals that the SiC/Al composites possess low density （2.94 g/cm^3）, high elastic modulus （220 GPa）, prominent thermal management function as a result of low coefficient of thermal expansion （8 × 10^4 K^-1） and high thermal conductivity （235 W/（m.K）） as well as unique preventability of resonance vibration. By adopting a series of developed techniques, the multi-functional SiC/Al composites have managed to be made into near-net-shape parts. Many kinds of precision components of space-based optomechanical structures and airborne optoelectronic platform have been turned out. Of them, several typical products are being under test in practices.展开更多
Topology optimization was developed as an advanced structural design methodology to generate innovative lightweight and high-performance configurations that are difficult to obtain with conventional ideas.Additive man...Topology optimization was developed as an advanced structural design methodology to generate innovative lightweight and high-performance configurations that are difficult to obtain with conventional ideas.Additive manufacturing is an advanced manufacturing technique building asdesigned structures via layer-by-layer joining material,providing an alternative pattern for complex components.The integration of topology optimization and additive manufacturing can make the most of their advantages and potentials,and has wide application prospects in modern manufacturing.This article reviews the main content and applications of the research on the integration of topology optimization and additive manufacturing in recent years,including multi-scale or hierarchical structural optimization design and topology optimization considering additive manufacturing constraints.Meanwhile,some challenges of structural design approaches for additive manufacturing are discussed,such as the performance characterization and scale effects of additively manufactured lattice structures,the anisotropy and fatigue performance of additively manufactured material,and additively manufactured functionally graded material issues,etc.It is shown that in the research of topology optimization for additive manufacturing,the integration of material,structure,process and performance is important to pursue high-performance,multi-functional and lightweight production.This article provides a reference for further related research and aerospace applications.展开更多
基金Foundation items： National Natural Science Foundation of China （50905144） State Key Laboratory of Materials Processing and Die ＆ Mould Technology, Huazhong University of Science and Technology （09-10）+2 种基金 NPU Foundation for Fundamental Research （JC201028） Fund of the State Key Laboratory of Solidification Processing in NWPU, Natural Science Basic Research Plan in Shaanxi Province （2011JQ6004） ＂111＂ Project （B08040）
文摘As one kind of key components with enormous quantities and diversities, the bent tube parts satisfy the increasing needs for lightweight and high-strength product from both materials and structure aspects. The bent tubes have been widely used in many high-end industries such as aviation, aerospace, shipbuilding, automobile, energy and health care. The tube bending has become one of the key manufacturing technologies for lightweight product forming. Via the analysis of bending characteristics and multiple defects, advances on exploring the common issues in tube bending are summarized regarding wrinkling instability at the intrados, wall thinning （cracking） at the extrados, springback phenomenon, cross-section deformation, forming limit and process/ tooling design/optimization. Some currently developed bending techniques are reviewed in terms of their advantages and limitations. Finally, in view of the urgent requirements of high-performance complex bent tube components with difficult-todeform and lightweight materials in aviation and aerospace fields, the development trends and corresponding challenges are presented for realizing the precise and high-efficiency tube bending deformation.
基金Foundation items： High-technology Research and Development Programme of China （2007AA03Z544） Aeronautical Science Foundation of China （20075221001）
文摘Multi-functional Al-matrix composites with high volume fraction （55%-57%） of SiC particles are produced with the new pressureless infiltration fabrication technology. X-ray detection and microscopic observation display the composites which are macroscopically homogeneous without porosity. The investigation further reveals that the SiC/Al composites possess low density （2.94 g/cm^3）, high elastic modulus （220 GPa）, prominent thermal management function as a result of low coefficient of thermal expansion （8 × 10^4 K^-1） and high thermal conductivity （235 W/（m.K）） as well as unique preventability of resonance vibration. By adopting a series of developed techniques, the multi-functional SiC/Al composites have managed to be made into near-net-shape parts. Many kinds of precision components of space-based optomechanical structures and airborne optoelectronic platform have been turned out. Of them, several typical products are being under test in practices.
基金supported by National Key Research and Development Program(2017YFB1102800)Key Project of NSFC(51790171,51761145111)NSFC for Excellent Young Scholars(11722219)。
文摘Topology optimization was developed as an advanced structural design methodology to generate innovative lightweight and high-performance configurations that are difficult to obtain with conventional ideas.Additive manufacturing is an advanced manufacturing technique building asdesigned structures via layer-by-layer joining material,providing an alternative pattern for complex components.The integration of topology optimization and additive manufacturing can make the most of their advantages and potentials,and has wide application prospects in modern manufacturing.This article reviews the main content and applications of the research on the integration of topology optimization and additive manufacturing in recent years,including multi-scale or hierarchical structural optimization design and topology optimization considering additive manufacturing constraints.Meanwhile,some challenges of structural design approaches for additive manufacturing are discussed,such as the performance characterization and scale effects of additively manufactured lattice structures,the anisotropy and fatigue performance of additively manufactured material,and additively manufactured functionally graded material issues,etc.It is shown that in the research of topology optimization for additive manufacturing,the integration of material,structure,process and performance is important to pursue high-performance,multi-functional and lightweight production.This article provides a reference for further related research and aerospace applications.
