| In aviation, military and other important fields , the complex thin-walled aluminum alloy parts are widely used for its unique comprehensive performance advantages. However, because the non-casting spare parts' poor rigidity characteristics and peel-type processing methods, processing precision and surface quality are difficult to be ensured and it is also difficult to improve processing efficiency, which greatly affect the economic efficiency of products and enterprises.Study the high-performance precision machining mechanism and technology of thin-walled aluminum alloy pieces has important theoretical significance and practical value.By the theoretical analysis and simulation studies of thin-walled aluminum alloy milling processing technology,this article aims to reveal the variation law of milling force with the changes of process parameters and study the release method of stress in thin-walled parts and Processing sequence in order to optimizing high-speed milling process parameters ,simplifying manufacturing processes, shortening production cycles, improving metal removal efficiency and giving full play to high-speed CNC machine tools.Study contents, specific works and the conclusions of this topic are as follows:First, the finite element cutting process simulation model was established. After described the related theories of metal-cutting deformation, including the cutting force, cutting heat, thermal coupling theory as well as the constitutive equation, the finite element simulation model was established to simulate the continuous formation process of aluminum alloy based on contact model of the chip - work-piece and tool -chip interface and the cutting material flow constitutive model. Meanwhile, distribution information of the cutting regional stress field, strain field and temperature field was given and the simulation results proved consistent with the actual situation.Second, cutting performance analysis and process parameters optimization of thin-walled pieces was studied. Caused by the milling speed feed rate and chip depth, the cutting forces and heat effects analyzed using single factor method. On this basis, in order to part accuracy and processing efficiency of multi-objective perspective study of milling dosage ratio, experiments show that increasing cutting speed feeding volume and reducing the cutting depth,it can reduce the amount of cutting force and increase the removal of the actual processing of the milling parameters ,which guided to the choice of role, and analysis of milling and cooling of the milling performance.Thirdly, based on error analysis process of thin-walled parts processing the order and margin optimization method. For the analysis of thin-walled sheet items in order to process the system stiffness as an entry point, according to processing location, machining allowance, and processes to develop parts of the process wall thickness obtained during processing operations shall not destroy the principle of the system stiffness to develop technology.Fourth, study the thin-walled parts to eliminate the stress method. Thin-walled parts during processing due to internal stress prone to elastic deformation, resulting in processing errors, the current method of eliminating stress is to have the main stress of passive components using vibration mode, while the major research paper during processing to prevent the parts stress generated, using the thin-wall parts on the layout of the stress release of the domain, to take the initiative to prevent the effect of, first of all to build from the theoretical model, demonstrated the feasibility of stress releasing holes, and then for the numerical simulation of a typical thin-walled parts to verify the appropriate stress the release of holes can be part deformation reduced 5-fold.Last, examples are illustrated. Block for the installation of aviation case study, according to the full text studies and draw process planning, validation aluminum alloy thin-walled parts in order and parameter optimization process is feasible.
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