| Titanium alloy is widely used in aerospace industry because of its excellent properties. Titanium alloy ring shell container serves for the fuel storage of space vehicle, which is used in some severe rugged environment and of high requirement of forming quality. But there exit a lot of forming difficulties during the manufacturing because the titanium alloy is valuable and hard to deform. These process problems are studied in the dissertation with computer numerical simulation combining with theoretical analysis. A brief introduction to the project and its main results are as follows:(1) After the thorough study of the titanium alloy ring shell forming process, a practical elasto-plastic FEM model is established and the key technologic problems are dealt with reasonably. The deforming body is dispersed by four-node quadrangular axial-symmetrical solid element; surface-to-surface contact element is used for creating the contact pair.(2) With the FEM simulation, the strain and stress of each node under different deformation stage are analyzed and the common forming law of this ring shell container is obtained. The results show that the nodes in the inner edge of the blank have the maximum strain and stress values, so the tearing failure is easy to occur here.(3) The distribution of the strain and stress with different thickness of the blanks are analyzed and the influence of the thickness on the deformation ability is discussed. Then the optimum thickness of initial blank is obtained for perfect forming part.(4) Based on the orthogonal experimental design, blanks with different size of inner and outer edge are selected and the forming processes under these conditions are simulated by FEM. The deformation gridding diagram and their strain and stress values are given. Based on which the influence law of the blank geometric parameters on the strain and the stress being analyzed, the optimum dimension of theblank is obtained by taking the vertical remain as research index value.
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