Material properties of blank have a great effect on power spinning process of aluminum alloy parts with transverse inner rib.By using finite element(FE) and Taguchi method,the effects and significance of five key material parameters,namely,anisotropic index in thickness direction,yield strength,hardening exponent,strengthening factor and elastic modulus on the formability of inner rib,tendency of wall fracture and degree of inhomogeneous deformation of finished spun parts were obtained.The achievements provide an important guide for selecting reasonable spinning material,and are very significant for the optimum design and precision control of power spinning process of parts with transverse inner rib.
During the splitting spinning process, the material parameters of disk blank have a significant effect on the determination of forming parameters and the quality of deformed blank. The influence laws of material parameters, including yield stress, hardening exponent and elastic modulus, on splitting spinning force, splitting spinning moment, degree of inhomogeneous deformation and quality of flange (average thickness and average deviation angle) were investigated by 3D-FE numerical simulation based on elasto-plastic dynamic explicit FEM under ABAQUS/Explicit environment. The results show that, the splitting spinning force and the splitting spinning moment increase with the increase of yield stress, hardening exponent and elastic modulus. The degree of inhomogeneous deformation increases with the decrease of yield stress and hardening exponent and the increase of elastic modulus. The average thickness of flange increases with the decrease of yield stress and the increase of hardening exponent and elastic modulus. The average deviation angle of upper surface increases with the increase of yield stress and the decrease of hardening exponent and elastic modulus. The average deviation angle of lower surface increases with the decrease of yield stress, hardening exponent and elastic modulus. Meanwhile, the corresponding variation ranges are given. The achievements may serve as an important guide for selecting the reasonable processing parameters of splitting spinning based on different aluminum alloys, and are very significant for optimum design and precision control of the splitting spinning process.
In order to improve the computational accuracy and efficiency,it is necessary to establish a reasonable 3D FEM model for multi-pass spinning including not only spinning process but also springback and annealing processes.A numerical model for multi-pass spinning is established using the combination of explicit and implicit FEM,with the advantages of them in accuracy and efficiency. The procedures for model establishment are introduced in detail,and the model is validated.The application of the 3D FEM model to a two-pass spinning shows the following：The field variables such as the stress,strain and wall thickness during the whole spinning process can be obtained,not only during spinning process but also during springback and annealing processes,and the trends of their distributions and variations are in good agreement with a practical multi-spinning process.Thus the 3D FEM model for multi-pass spinning may be a helpful tool for determination and optimization of process parameters of multi-pass spinning process.
