A Study on Combined Numerical Analysis Model and experiment of Shape Rolling Processes

• Main Authors: Lin, Hong-Ren, 林鴻仁
• Other Authors: Hsiang Su-Hai
• Format: Others
• Language: zh-TW
• Published: 1996
• Online Access: http://ndltd.ncl.edu.tw/handle/98626218085236947335

碩士 === 國立台灣工業技術學院 === 機械工程技術研究所 === 84 === The object of this paper is to develop a simulation model to analyze thedeformation behavious of material under Shape Rolling. The Combined NumericalAnalysis Method is used in this study, which combined the merits of the FiniteElement Method( FEM) and the Slab Method. In dealing with the large deformationproblems, it has the merits of high accuracy and efficiency. Besides,under theassumption of the roll is a rigid body,this model can effectively analyzed thethree dimensional steady-state deformation of the materials under rolling. The material is divided into several elements which are in the from of 8-node hexahedral isoparametric elements. In shape rolling process, the materialis assumed to be a rigid-plastic body with uniform thickness. The distributionof velocity and the equivalent strain-rate can be calculaed from the velocityat nodal points and the functional can be minimized by the variation of thevelocity at all nodal points.The streamlines and the distribution of thicknesscan be obtained from the velocity field and boundary condition. More over, thedistribution of the eqivalent strain of the initial streamlines can be foundby integrating the eqivalent strain rate along the streamlines with the SlabMethod.Then,the flow stress can be sloved.On the assumption of the streamlinesto be the boundaries of the element, the mesh of new element can be generated.The rigid- plastic finite element method is applied to slove the mesh of newelement and the distribution of flow stress curve, and the distribution ofvelocity,stress,strain and strain rate of the element can be calculated.Repeatthe above procedures until the calculated result converges to the assumedcondition, the analytical results of the steady-state deformation can beobtained. In order to verify the availability of the developed numerical simulationmodel, some experiments of shape rolling are executed,and it show good coinci-dence with the analytical results.