Aiming at the exploration and resource utilization activities on the Moon,in situ resource utilization and in situ manufacturing are proposed to minimize the dependence on the ground transportation supplies.In this pa...Aiming at the exploration and resource utilization activities on the Moon,in situ resource utilization and in situ manufacturing are proposed to minimize the dependence on the ground transportation supplies.In this paper,a laser-assisted additive manufacturing process is developed to fabricate lunar regolith composites with PA12/SiO2 mixing powders.The process parameters and composite material compositions are optimized in an appropriate range through orthogonal experiments to establish the relationship of process–structure–property for lunar regolith composites.The optimal combination of composite material compositions and process parameters are mixing ratio of 50/50 in volume,laser power of 30 W,scanning speed of 3500 mm/s,and scanning hatch space of 0.2 mm.The maximum tensile strength of lunar regolith composites reaches 9.248 MPa,and the maximum depth of surface variation is 120.79μm,which indicates poor powder fusion and sintering quality.Thereafter,the mechanical properties of laser-sintered lunar regolith composites are implemented to the topology optimization design of complex structures.The effectiveness and the feasibility of this laser-assisted process are potentially developed for future lightweight design and manufacturing of the solar panel installed on the lunar rover.展开更多
To compensate for the imperfection of traditional bi-directional evolutionary structural optimization, material interpolation scheme and sensitivity filter functions are introduced. A suitable filter can overcome the ...To compensate for the imperfection of traditional bi-directional evolutionary structural optimization, material interpolation scheme and sensitivity filter functions are introduced. A suitable filter can overcome the checkerboard and mesh-dependency. And the historical information on accurate elemental sensitivity numbers are used to keep the objective function converging steadily. Apart from rational intervals of the relevant important parameters, the concept of distinguishing between active and non-active elements design is proposed, which can be widely used for improving the function and artistry of structures directly, especially for a one whose accurate size is not given. Furthermore, user-friendly software packages are developed to enhance its accessibility for practicing engineers and architects. And to reduce the time cost for large timeconsuming complex structure optimization, parallel computing is built-in in the MATLAB codes. The program is easy to use for engineers who may not be familiar with either FEA or structure optimization. And developers can make a deep research on the algorithm by changing the MATLAB codes. Several classical examples are given to show that the improved BESO method is superior for its handy and utility computer program software.展开更多
基金This work was supported by the National Key R&D Program of China(Grant No.2017YFB1102800)the National Natural Science Foundation of China for Excellent Young Scholars(Grant No.11722219)+1 种基金the National Natural Science Foundation of China(Grant No.51905439)the Emerging(Interdisciplinary)Cultivation Project of Northwestern Polytechnical University,China(Grant Nos.19SH030403 and 20SH030201).
文摘Aiming at the exploration and resource utilization activities on the Moon,in situ resource utilization and in situ manufacturing are proposed to minimize the dependence on the ground transportation supplies.In this paper,a laser-assisted additive manufacturing process is developed to fabricate lunar regolith composites with PA12/SiO2 mixing powders.The process parameters and composite material compositions are optimized in an appropriate range through orthogonal experiments to establish the relationship of process–structure–property for lunar regolith composites.The optimal combination of composite material compositions and process parameters are mixing ratio of 50/50 in volume,laser power of 30 W,scanning speed of 3500 mm/s,and scanning hatch space of 0.2 mm.The maximum tensile strength of lunar regolith composites reaches 9.248 MPa,and the maximum depth of surface variation is 120.79μm,which indicates poor powder fusion and sintering quality.Thereafter,the mechanical properties of laser-sintered lunar regolith composites are implemented to the topology optimization design of complex structures.The effectiveness and the feasibility of this laser-assisted process are potentially developed for future lightweight design and manufacturing of the solar panel installed on the lunar rover.
基金supported by the National Natural Science Foundation of China(No.51078311)
文摘To compensate for the imperfection of traditional bi-directional evolutionary structural optimization, material interpolation scheme and sensitivity filter functions are introduced. A suitable filter can overcome the checkerboard and mesh-dependency. And the historical information on accurate elemental sensitivity numbers are used to keep the objective function converging steadily. Apart from rational intervals of the relevant important parameters, the concept of distinguishing between active and non-active elements design is proposed, which can be widely used for improving the function and artistry of structures directly, especially for a one whose accurate size is not given. Furthermore, user-friendly software packages are developed to enhance its accessibility for practicing engineers and architects. And to reduce the time cost for large timeconsuming complex structure optimization, parallel computing is built-in in the MATLAB codes. The program is easy to use for engineers who may not be familiar with either FEA or structure optimization. And developers can make a deep research on the algorithm by changing the MATLAB codes. Several classical examples are given to show that the improved BESO method is superior for its handy and utility computer program software.
