Backward spinning is analyzed by 3D rigid-plastic FEM.A 3D mechanical model for backward spinning is presented. The distributions are obtained of strain一rate and stress in the con- tact area of the roller a...Backward spinning is analyzed by 3D rigid-plastic FEM.A 3D mechanical model for backward spinning is presented. The distributions are obtained of strain一rate and stress in the con- tact area of the roller and its adjacent area.The results can well intemret the principle of defonnation of backward spinning. The relationship between the roller angle and three components ofspinning force is found out, and the optimum roller angle, when the general spinning foree gets to the minimum value, is calculated. The distributions of defonnation area obtained by FEM agree with the experimental result well.展开更多
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 param...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.展开更多
The residual stress distribution of Hastelloy C corrosion-resistant alloy tubes after power spinning was simulated with the elasto-plastic finite element method combining with the element birth and death technique, th...The residual stress distribution of Hastelloy C corrosion-resistant alloy tubes after power spinning was simulated with the elasto-plastic finite element method combining with the element birth and death technique, the influences of spinning parameters on the distribution of the residual stress were investigated in detail, and the formation mechanism of residual stress during tube spinning was discussed. Based on the calculation of the residual stress, the reasons for annealing cracks on the spun tube during interpass heat treatment were explored. The simulation results and the characteristics of annealing cracks show that the circumferential residual tensile stress is a main factor to cause the annealing cracks.展开更多
文摘Backward spinning is analyzed by 3D rigid-plastic FEM.A 3D mechanical model for backward spinning is presented. The distributions are obtained of strain一rate and stress in the con- tact area of the roller and its adjacent area.The results can well intemret the principle of defonnation of backward spinning. The relationship between the roller angle and three components ofspinning force is found out, and the optimum roller angle, when the general spinning foree gets to the minimum value, is calculated. The distributions of defonnation area obtained by FEM agree with the experimental result well.
基金Projects(50405039, 50575186) supported by the National Natural Science Foundation of ChinaProject(50225518) supported by the National Science Foundation of China for Distinguished Young ScholarsProject supported by the Foundation of Northwestern Polytechnical University, China
文摘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.
基金the National Natural Science Foundation of China(No.59995444).
文摘The residual stress distribution of Hastelloy C corrosion-resistant alloy tubes after power spinning was simulated with the elasto-plastic finite element method combining with the element birth and death technique, the influences of spinning parameters on the distribution of the residual stress were investigated in detail, and the formation mechanism of residual stress during tube spinning was discussed. Based on the calculation of the residual stress, the reasons for annealing cracks on the spun tube during interpass heat treatment were explored. The simulation results and the characteristics of annealing cracks show that the circumferential residual tensile stress is a main factor to cause the annealing cracks.
