Analytical Model for Predicting Sheet Springback
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Analytical model for predicting sheet springback
Submitted By: shaikh afroz
123374002
Department of Metallurgical Engineering and Materials Science
INDIAN INSTITUTE OF TECHNOLOGY, BOMBAY
1) Introduction
As an important manufacturing method, bending has been widely used in modern industries to produce stamping parts such as frames, channels, braces, brackets and other structural parts. The understanding and development of bending mechanics are aimed at achieving two kinds of information which are very important for industrial production. One is to predict springback for dies design and compensation in order to obtain high dimension accuracy of bending parts. The other is to determine the limit bending ratio Ri/t0 for a given sheet thickness and material properties. Different methods such as analytical method, semi-analytical method and finite element method (FEM) have been applied to analyze the bending process. FEM is a time-consuming method and also is very sensitive to numerical parameters such as element type and size, algorithms, contact definition and convergence criterion for solution, etc. Analytical method is a time-saving method and has been widely used for predicting springback of bending parts. But most of these researches ignored the effects of contact pressure, transverse stress, neutral surface shifting and thickness thinning on sheet springback of bending parts. Previous research ignored the effect of neutral surface shift and contact pressure between the sheet and die, they were limited to the springback problem of bending ratio Ri/t0 ≥5. For the bending ratio Ri/t0≥5, the effects of contact pressure, transverse stress, neutral surface shifting on sheet springback of bending are significant, with the analysis models which ignore them being inaccurate as the bending ratio decreases. An analytical model to predict the sheet springback of V-bending has been studied. This model is based on Hill’s yielding criterion and plane
Analytical model for predicting sheet springback
Submitted By: shaikh afroz
123374002
Department of Metallurgical Engineering and Materials Science
INDIAN INSTITUTE OF TECHNOLOGY, BOMBAY
1) Introduction
As an important manufacturing method, bending has been widely used in modern industries to produce stamping parts such as frames, channels, braces, brackets and other structural parts. The understanding and development of bending mechanics are aimed at achieving two kinds of information which are very important for industrial production. One is to predict springback for dies design and compensation in order to obtain high dimension accuracy of bending parts. The other is to determine the limit bending ratio Ri/t0 for a given sheet thickness and material properties. Different methods such as analytical method, semi-analytical method and finite element method (FEM) have been applied to analyze the bending process. FEM is a time-consuming method and also is very sensitive to numerical parameters such as element type and size, algorithms, contact definition and convergence criterion for solution, etc. Analytical method is a time-saving method and has been widely used for predicting springback of bending parts. But most of these researches ignored the effects of contact pressure, transverse stress, neutral surface shifting and thickness thinning on sheet springback of bending parts. Previous research ignored the effect of neutral surface shift and contact pressure between the sheet and die, they were limited to the springback problem of bending ratio Ri/t0 ≥5. For the bending ratio Ri/t0≥5, the effects of contact pressure, transverse stress, neutral surface shifting on sheet springback of bending are significant, with the analysis models which ignore them being inaccurate as the bending ratio decreases. An analytical model to predict the sheet springback of V-bending has been studied. This model is based on Hill’s yielding criterion and plane
References: 1. Buranathiti T., Cao. J, An effective analytical model for springback prediction in straight flanging processes. International Journal of Materials and Product Technology, 2004 , 21, 137-153 2. Gabriele Papadia, Antonio Del Prete, Experimental springback evaluation in hydromechanical deep drawing (HDD) of large products, Academic Society for Production Engineering, 2012, 6, 117–127 3. Daw-Kwei Leu, Position deviation in V-die bending process with asymmetric bend length, International Journal of Advanced Manufacturing Technology, 2012, 12, 3998-2