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In order to satisfy the machining requirements of aero-engine casing in modern aviation industry, this paper investigates three main issues during the design and development process of a five-axis machine tool with high accuracy, stiffness and efficiency, including whole structure design,key components design, and supporting stiffness design. First, an appropriate structure of five-axis machine tool is determined considering the processing characteristics of aero-engine casing. Then, a dual driv... 相似文献
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《中国航空学报》2023,36(7):129-146
In the quest for decreasing fuel consumption and resulting gas emissions in the aeronautic sector, lightweight materials such as Carbon Fiber Reinforced Polymers (CFRPs) and Ti-6Al-4V alloys are being used. These materials, with excellent weight-to-strength ratios, are widely used for structural applications in aircraft manufacturing. To date, several studies have been published showing that the use of metalworking fluids (MWFs), special tool geometries, or advanced machining techniques is required to ensure a surface quality that meets aerospace component standards. Conventional MWFs pose a number of environmental and worker health hazards and also degrade the mechanical properties of CFRPs due to water absorption in the composite. Therefore, a transition to more environmentally friendly cooling/lubrication techniques that prevent moisture problems in the composite is needed. This research shows that lubricated LCO2 is a viable option to improve the quality of drilled CFRP and titanium aerospace components compared to dry machining, while maintaining clean work areas. The results show that the best combination of tool geometry and cooling conditions for machining both materials is drilling with Brad point drills and lubricated LCO2. Drilling under these conditions resulted in a 90 % improvement in fiber pull-out volume compared to dry machined CFRP holes. In addition, a 33 % reduction in burr height and a 15 % improvement in surface roughness were observed compared to dry drilling of titanium. 相似文献
605.
轻量化技术是指在满足结构性能需求的前提下,通过对材料、结构和制造工艺等方面的优化,减少结构质量的技术,已经成为新一代航空航天装备发展的关键技术之一。本文首先分析了轻量化技术的发展历程。其次,从设计原理、组成方式和优化方法角度,介绍了仿生结构设计、胞元结构设计和高效拓扑优化设计三类轻量化设计方法。然后,从轻量化制造工艺和模式的角度阐述了增材制造、协同制造和复合材料制造在航空航天结构轻量化制造中的应用。最后,讨论了轻量化技术面临的挑战和未来的发展。 相似文献
606.
《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2023,71(6):2656-2668
In-Situ Fabrication and Repair can significantly reduce the construction cost of a permanent Moon base by using additive manufacturing (AM) and exploiting local resources instead of bringing all the required materials from Earth. In this article, we evaluate alternative additive manufacturing technologies for building a lunar base and maintaining it across its lifecycle. We compare alternative 3D-printing techniques, already tested for manufacturing with simulants of lunar regolith, using energy, Earth-deliverables consumption, and compressive strength of the produced samples as figures of merit. Based on our analysis, we conclude that Cement Contour Crafting and Stereo-lithography AM techniques are the most promising solutions for the construction of outdoor lunar infrastructure and small precise parts and instruments, respectively. 相似文献
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《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2023,71(5):2175-2185
As researchers continue to study methods to facilitate long-term missions beyond low-Earth orbit, the ability to manufacture high-quality mechanical and structural components on the Lunar and Martian surfaces remains a crucial piece to the puzzle for a sustained presence. Due to the immense cost of sending supplies to extraterrestrial bodies, in-situ resource utilization (ISRU) methods are critical for the success and feasibility of these habitation missions. Ionic liquids (ILs) are currently being studied at NASA’s Marshall Space Flight Center (MSFC) to harvest elemental metals from meteorites and regolith minerals. Additionally, the Bosch process is being explored as a life support system at MSFC for oxygen (O2) regeneration, rendering a byproduct of elemental carbon (C). In this investigation, the viability of casting ductile iron (DI) using IL-sourced iron (IL-Fe) and Bosch C was studied given the range of applications and performance of DI as an as-cast alloy. Ingots were produced using commercial elements to simulate the use of IL-Fe with C sourced from the byproduct C of the Bosch process. Samples were cast and compared to commercially available 65–45-12 DI with phase transformation diagrams, microstructures, and hardness. Results showed that IL-sourced elements are a viable source of elemental alloying materials for a range of DI alloys, with some limitations. 相似文献
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宁振波 《民用飞机设计与研究》2021,(2):1-5
智能制造包含智能制造技术和智能制造系统,是国际上公认的实现工业体系转型升级的新一代方法论,能够从根本上提升我国复杂产品的创新能力和研制水平,因此,正确理解、全面认识智能制造,对我国的经济发展、数字中国的建设具有极其重大的现实意义和历史意义.智能制造的基础是数字化,由于航空工业具有复杂性、可靠性、研制成本高的三高特征,因... 相似文献