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671.
针对电解加工多孔表面特点,提出表面形貌评价指标,获取多孔表面图像并对其进行预处理,提取腐蚀率、不均匀度、灰度等特征参数,揭示各特征参数与电解加工多孔表面形貌的相关性,并通过实例证明该方法适用于电解加工多孔表面的测量。 相似文献
672.
Machining performance of thin-walled components made by aeronautical difficult-toprocess materials is a significant issue in the aviation manufacturing industry. Although wire electric discharge machining-low speed(WEDM-LS) is one of typical non-contact machining processes without macro cutting force, which does well in removing hardness and brittleness materials via pulsed discharge at high temperature, but few researchers have studied the thermal distortion behavior leading to a considerable g... 相似文献
673.
《中国航空学报》2021,34(2):641-658
Solving the shortest tool length quickly under a known tool trajectory in multi-axis machining of complex channel parts is an urgent problem in industrial production. To solve this problem, a novel and efficient method is proposed which is featured by extracting only a few necessary curves from the check surface instead of sampling the entire surface. By rotating and compressing the 3D check surface relative to all tool postures, the boundaries of the area occupied by the 2D compressed surfaces are the essential elements for determining the shortest tool length. A tracking-based numerical algorithm is introduced to efficiently solve the silhouette curves which are formed in compressing. To define the multi-taper shaped tool holding system (THS) which is commonly used in production, a characterization model for THS profile is established. A model for solving the shortest tool length is finally constructed based on the critical interference relationship between the THS profile and all compressed boundary curves. For acceleration, the boundary splines are segmented according to their knot vectors. Then a new concept called the axis-aligned tool length box (AATB) is introduced, which can provide a conservative range of tool length for a spline segment. By scanning the AATBs of all spline segments, the very few effective spline segments that may ultimately determine the shortest tool length are filtered out. This acceleration method makes the solution for the shortest tool length more focused and efficient. The results of experimental examples are also reported to validate the efficiency and accuracy of the proposed algorithm. 相似文献
674.
将基于UG平台动态装配技术的加工过程几何仿真与基于MATLAB平台有限元分析的成形规律仿真有机结合,实现了整体构件上复杂曲面、型腔数控电解加工过程的计算机仿真,用于加工试验前的加工过程干涉检查、阴极及其运动轨迹优化设计、优选加工参数及成形精度分析等,能有效缩短准备周期、减少试验次数。该技术已经应用于航空发动机关键零件加工准备过程,具有重要工程实用价值。 相似文献
675.
以航空壳体类零件为研究对象,分析该类零件的结构特点,利用UG和VERICUT的功能,形成了一套航空壳体类零件虚拟加工仿真方法。 相似文献
676.
航空金属滤网的特种加工技术(英文) 总被引:3,自引:0,他引:3
Thanks to recent advances in manufacturing technology, aerospace system designers have many more options to fabricate high-quality, low-weight, high-capacity, cost-effective filters. Aside from traditional methods such as stamping, drilling and milling, many new approaches have been widely used in filter-manufacturing practices on account of their increased processing abilities. How- ever, the restrictions on costs, the need for studying under stricter conditions such as in aggressive fluids, the complicity in design, the workability of materials, and others have made it difficult to choose a satisfactory method from the newly developed processes, such as, photochemical machining (PCM), photo electroforming (PEF) and laser beam machining (LBM) to produce small, inexpensive, lightweight aerospace filters. This article appraises the technical and economical viability of PCM, PEF, and LBM to help engineers choose the fittest approach to turn out aerospace filters. 相似文献
677.
678.
《中国航空学报》2023,36(4):523-537
Electrochemical machining (ECM) has emerged as an important option for manufacturing the blisk. The inter-electrode gap (IEG) distribution is an essential parameter for the blisk precise shaping process in ECM, as it affects the process stability, profile accuracy and surface quality. Larger IEG leads to a poor localization effect and has an adverse influence on the machining accuracy and surface quality of blisk. To achieve micro-IEG (<50 μm) blisk finishing machining, this work puts forward a novel variable-parameters blisk ECM strategy based on the synchronous coupling mode of micro-vibration amplitude and small pulse duration. The modelling and simulation of the blisk micro-IEG machining have been carried out. Exploratory experiments of variable-parameters blisk ECM were carried out. The results illustrated that the IEG width reduced with the progress of variable parameter process. The IEG width of the blade’s concave part and convex part could be successfully controlled to within 30 μm and 21 μm, respectively. The profile deviation for the blade’s concave surface and convex surface are 49 μm and 35 μm, while the surface roughness reaches Ra = 0.149 μm and Ra = 0.196 μm, respectively. The profile accuracy of the blisk leading/trailing edges was limited to within 91 μm. Compared with the currently-established process, the profile accuracy of the blade’s concave and convex profiles was improved by 50.5 % and 53.3 %, respectively. The surface quality was improved by 53.2 % and 50.9 %, respectively. Additionally, the machined surface was covered with small corrosion pits and weak attacks of the grain boundary due to selective dissolution. Some electrolytic products were dispersed on the machined surface, and their components were mainly composed of the carbide and oxide products of Ti and Nb elements. The results indicate that the variable-parameters strategy is effective for achieving a tiny IEG in blisk ECM, which can be used in engineering practice. 相似文献
679.
680.
Ahmed Mohamed Mahmoud IBRAHIM Wei LI Abdel-Hamid ISMAIL MOURAD Mohamed A.E.OMER Fadl A.ESSA Ahmed Mustafa ABD EL-NABY Mohammad S.Al SOUFI Muhammad F.EZZAT Ammar ElSHEIKH 《中国航空学报》2023,36(7):76-113
Grinding technology is an essential manufacturing operation, in particular, when a component with a superfinishing and an ultra-resolution is yearned. Meeting the required strict quality checklist with maintaining a high level of productivity and sustainability is a substantive issue. The recent paper outlines the lubrication and cooling technologies and mediums that are used for grinding. Furthermore, it provides a basis for a critical assessment of the different lubrication/cooling techniques ... 相似文献