| A blade is one of the most important mechanical components in an aero-engine. Precision forging of blade is a tendency to develop blade forging technology. However, the blade is complicated in shape, and its material used is difficult to deform. Up to now, there has not been a thorough study and understanding of the precision forging process of blade and forming law. Therefore, it is important to systematically and through research on precision forging process of blade for the optimization of precision forging technology and design of dies and the development of its precision forging by using 3-D FEM numerical simulation. A brief introduction to the project and its main results are as follows: Based on a through study of the key technical problems of 3D rigid-plastic and rigid-viscoplastic FEM simulation of blade forging process, using 3D-PFS (3D Plastic Forming Simulation)developed by our laboratory as a platform, a simulation system 3D-PFS-1 has been developed for simulation and analysis of forging process of blade with a tenon, one of the important types of the blade, which makes it possible to accurately understand an influence of precision forging conditions on the precision forging process and forming laws. The system, using a modular approach, has a friendly function of pre-processing and post-processing, can be easily extended and explanted, and can also be popularized to finite element simulation and analysis of other complex massive forming process. A 3D FEM simulation mechanics model corresponding to reality has been proposed for the precision forging process of the blade. A simulation and analysis has been carried out by using 3D-PFS-1 for precision forging process of blade with a tenon, and the results have been obtained for deformed mesh, velocity field, equivalent stress field, equivalent strain field and load stroke curve at various deformation degrees. The research shows that, the distribution of equivalent strain,equivaleni strCss and equivalent strain rate are extremely uneven in the precisionforging process of blade with a tenon; the deformation in the tenon is smallef, and thedeformation in the blade body is larger; and the deformation in the center of the bladebody is largest.Based on the arctangent fimction frictional model, a simulation and study of aninfluence of friction along die-material interface on the precision fOrging process ofblade has been carried out by using 3D-PFS-l. The results show the following: (l) thedeformation in tenon is hardly affected by hiction, but the deformation in blade bodynotably varies wtth various friction conditions; (2) the larger the ffiction factor, themore even the metal fiow toward the left and right of the die cavity, the easier alongthe lateral direction, and the more difficult along the longitudinal direction of theblade body, and vice versa, (3) with an increase of the friction factor, the distributiongradient of equivalent strain, equivalent strain rate and equivalent stress becomegreater in the defOrmation of the blade body.By using the system, a simulation and study of an influence of shaPe, dimension,and position in the die of pre-form billets on the precision forging process of bladehas been carried out. A reasonable shaPe, dimension and position from pre-formbillets have been given by combining compensation principle of deformation with 3Drigid-viscoplastic FEM fOrward simulation, Which provide a theory basis fOr therelated practice of the precision fOrging of blade with a tenon.Using plasticine as modeling material, physical modeling has been cAned outby means of a method of locally making layer-built billet fOr the blade fOrgingprocess. A good agreement of numerical simula...
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