FEM Analysis during Extrusion of Round-To-Pentagonal Sections through Converging Dies

2012 ◽  
Vol 500 ◽  
pp. 410-413
Author(s):  
Akshaya Kumar Rout ◽  
Kali Pada Maity

The linearly converging die plays a significant role in the extrusion process of section products in terms of reduction in extrusion load and improvement of product quality. With the help of upper bound method based on dual stream function method. Very few investigations have been reported when product and billet geometry are dissimilar using linear converging die. Dual stream function method is incapable of predicting kinematically admissible velocity field in the above case, SERR technique (Spatial Elementary Rigid Region) is the only alternative. In the present investigation, a reformulated SERR technique has been used to determine non-dimensional extrusion pressure and optimum die profile both for frictionless and friction conditions. SERR technique based on discontinuous velocity field is applicable for this case. In the present investigation, non-dimensional extrusion pressure and optimum die length has been determined for extrusion of pentagonal from round billet and the results are compared with the FEA results by using DEFORM 3D.

2009 ◽  
Vol 424 ◽  
pp. 181-188 ◽  
Author(s):  
Kali Pada Maity ◽  
Akshaya Kumar Rout ◽  
Kalu Majhi

Extrusion through mathematically contoured die plays a critical role in improvement of surface integrity of extruded product. There is gradual deformation which results in the uniform microstructure. In the present investigation non-dimensional extrusion pressure and optimum die length for cosine die profile has been obtained by three dimensional upper bound method using dual stream function method for different reductions. The theoretical modeling has been validated with experiments. The experimental results are found to be compatible with the theory.


Author(s):  
JG Ding ◽  
HY Wang ◽  
DH Zhang ◽  
DW Zhao

In this paper, three-dimensional velocity field is proposed by means of stream function method with bisecting yield criterion in chamfer edge rolling of ultra-heavy plate. Parabolic dog-bone shape function is derived so as to obtain velocity field with fixed angle of chamfer edge by stream function method, dog-bone shape coefficient η can be derived from volume invariant condition, and then the plastic deformation power, shear power as well as friction power are obtained respectively with the bisecting yield criterion. Summing up the power contributions, total power functional is presented, from which minimum value can be obtained by searching method, and vertical rolling force and torque are also finally obtained. The predictions of roll force and torque are compared with different angles of chamfer edge as well as different plate thicknesses. The results are shown to be in a very good agreement with the analytical and experimental results.


2014 ◽  
Vol 622-623 ◽  
pp. 1215-1220
Author(s):  
Jarosław Bartnicki ◽  
Janusz Tomczak ◽  
Zbigniew Pater

This paper presents results of numerical calculations of rolling extrusion process of a toothed shaft made from titanium alloy Ti6Al4V. FEM analysis was conducted applying the software DEFORM 3D for the process chosen technological parameters. The kinematics of metal flow in the area of the formed teeth was analyzed. Distributions of stresses, strains and temperatures during teeth forming were determined. Calculated values of axial and radial forces and moments acting on rotating roll tools allow for designing of tools for experimental verification of the designed forming process.


1987 ◽  
Vol 109 (2) ◽  
pp. 161-168 ◽  
Author(s):  
D. Y. Yang ◽  
C. H. Han

A new analytic method is proposd for estimating the extrusion pressure, the final effective strain of the extruded billet, and the grid distortion patterns in axisymmetric forward extrusion through arbitrarily curved dies. A generalized kinematically admissible velocity field is derived to formulate an upper-bound solution. The corresponding upper-bound extrusion pressure is then obtained by optimizing the process parameters. The effects of area reduction, frictional condition, die length, and the die profile are discussed in relation to the extrusion pressure, the distorted grid pattern, and distribution of the final effective strain on the cross-section of the extruded billet. In the computation a biquadratic polynomial is chosen for the die profile. The work-hardening effect is incorporated in the formulation. Experiments are carried out for AISI 4140 steel billets at room temperature. The theoretical predictions both in the extrusion load and deformed configuration are in excellent agreement with the experimental results and the results computed by the finite element method.


2011 ◽  
Vol 189-193 ◽  
pp. 1778-1781 ◽  
Author(s):  
Gui Hua Liu ◽  
Yong Qiang Guo ◽  
Zhi Jiang

By using Deform-3D software, the necking extrusion forming processes of integer trailer axle with two different heating means which are Uniform Heating (UH) method and Partly Heating (PH) method with temperature gradient are simulated. The influence of deformation parameters such as friction factor, necking coefficient, different temperature distribution of work-piece on the material flow features, stress and strain field, loading force and deformation process are analyzed in detail. According to the numerical simulation results, using PH method with temperature gradient can improve necking deformation during tube extrusion process.


2014 ◽  
Vol 217-218 ◽  
pp. 201-207
Author(s):  
Chun Fang Wang ◽  
Kai Kun Wang ◽  
Zhe Luo

Flexible thixo-extrusion, as an innovative near-net-shape forming method, has huge advantages in processing the components with complex geometry. However, it should keep in mind that conventional liquid casting still represents the dominant mean of aluminum alloys production. One of the obstacles the thixo-extrusion has to overcome is lack of proof that can live up to the claim that thixo-extruded components have better mechanical properties. The main aim of this paper is to simulate the flexible thixo-extrusion process of aluminum alloy A356 and investigate the control method of materials flow front. An isothermal compression test of aluminum alloy A356 is first conducted to obtain the true stress-strain curves at different temperatures and strain rates. A constitutive equation describing the relationship of stress, strain, strain rate and temperature is fitted by Origin and then imported to the DEFORM-3D simulation software. The results show that the quality of final component is enormously influenced by the radius of the arcs and the flexible thixo-extruded components has less defects compared with the conventional extruded ones.


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