Physical and Numerical Modelling of Wire Drawing Process of Mg Alloys in Heated Dies Accounting for Recrystallization

2014 ◽  
Vol 622-623 ◽  
pp. 651-658 ◽  
Author(s):  
Andrij Milenin ◽  
Piotr Kustra ◽  
Maciej Pietrzyk
Keyword(s):  
Mathematical Model ◽  
Tensile Tests ◽  
Wire Drawing ◽  
Complex Model ◽  
Mg Alloys ◽  
Drawing Process ◽  
Fracture Models ◽  
Body Production ◽  
Thermal Phenomena ◽  
Bio Compatibility

Magnesium-calcium alloys with increased bio-compatibility are applied in medicine for sake of high compatibility and solubility in human body. Production of surgical threads to integration of tissue may be one of the applications of those types of alloys. A new manufacturing process of thin wires made of biocompatible Mg alloys, including drawing in heated dies, was developed in Authors previous works. Conducting drawing process in conditions, in which recrystallization occurs, is the basis of the process. This allows for multi-pass drawing without intermediate annealing. Control of recrystallization after every pass using experimental method is complex so numerical simulation seems to be a rational method to design the process parameters. The purpose of the paper is developing a mathematical model of recrystallization for MgCa08 alloy, its implementation into the finite element (FE) code that simulates wire drawing and experimental verification of the numerical calculations. The first part of work was focused on the development of mathematical model of wire drawing process of Mg alloys in heated die. Proposed model takes into account thermal phenomena in the wire and in the die, plastic flow of the material, stress-strain state and recrystallization. The fracture criterion was implemented into FE code to eliminate the possibility of damage. The second part of the work was focused on experiments including upsetting and tensile tests for calibration of recrystallization and fracture models. Recrystallization model was calibrated on the basis of flow curves only what is a limitation. Therefore, experimental wire drawing on drawing bench developed by the Authors was the final stage of the work performed to validate the model. Recrystallization during wire drawing was studied. The developed computer program enables prediction of the recrystallization kinetics during wire drawing in heated die for MgCa08 alloy. The model of static and dynamic recrystallization of this alloy and complex model of the drawing process were proposed in this work, as well.

Bilinear damage evolution in AA2011 wire drawing processes

2022 ◽  
pp. 105678952110725
Author(s):  
Álvaro A González ◽  
Marcela A Cruchaga ◽  
Diego J Celentano
Keyword(s):  
Material Characterization ◽  
Damage Evolution ◽  
Mechanical Response ◽  
Tensile Tests ◽  
Wire Drawing ◽  
Drawing Process ◽  
Effective Plastic Strain ◽  
Predictive Capability ◽  
Two Parameters ◽  
Good Agreement

This paper presents an experimental and numerical analysis of damage evolution in AA2011 aluminum alloy wires drawn under different scenarios. To this end, load-unload tensile tests were firstly carried out in order to characterize the degradation of the mechanical response in every cycle where the experimental results show a bilinear damage relationship in terms of the effective plastic strain. Therefore, a modification of the classical Lemaitre model is proposed in this work in order to reproduce bilinear paths of damage with the addition of only two parameters that can be directly obtained from the material characterization. Then, the damage predictive capability of this new experimental-based model is assessed in numerical simulations of the drawing process in one and two passes (considering for this last case the sequential and tandem configurations) where the computed predictions are compared with the corresponding experimental data showing a good agreement between them.

scholarly journals An inverse analysis to identify the Johnson-Cook constitutive model parameters for cold wire drawing process

2020 ◽  
Vol 21 (5) ◽  
pp. 527
Author(s):  
Ashkan Mahmoud Aghdami ◽  
Behnam Davoodi
Keyword(s):  
Strain Rate ◽  
Objective Function ◽  
Inverse Analysis ◽  
Static Condition ◽  
Tensile Tests ◽  
Wire Drawing ◽  
Material Behavior ◽  
Model Parameters ◽  
Drawing Process ◽  
Cold Wire

Johnson-Cook constitutive equation was utilized to model the 10100 copper and AA 1100 aluminum wires at the cold wire drawing process. Initial Johnson cook parameters were determined through quasi-static tensile tests at different strain rates. Analytical and finite element with VUHARD subroutine solutions were implemented to calculate the drawing forces using the Johnson cook parameters. Wire drawing experiments were carried out at different drawing conditions with two areal reductions and four drawing speeds with the strain rate ranged from 37 s−1 to 115 s−1 and wire drawing forces were measured using a load cell connected to the drawing die. Results showed that the Johnson cook model with parameters determined from a quasi-static condition was not able to predict the material behavior at the wire drawing process with a moderate strain rate. In order to modify the initial JC parameters an inverse analysis approach was adopted. An objective function was defined based on analytical and experimental drawing forces differences with respect to JC parameters. Using the Newton–Raphson method, new JC parameters were identified by minimizing the objective function. Updated Johnson cook parameters showed much more correlation with experimental results.

Optimization of Deep Drawing Processes Using Statistical Design of Experiments

1996 ◽  
Author(s):  
Dietrich Bauer ◽  
Regine Krebs
Keyword(s):  
Mathematical Model ◽  
Analysis Of Variance ◽  
Orthogonal Array ◽  
Deep Drawing ◽  
Metal Forming ◽  
Drawing Process ◽  
Drawing Force ◽  
Forming Process ◽  
Deep Drawing Process ◽  
Metal Forming Process

Abstract For a deep drawing process some important controllable variables (factors) upon the maximum drawing force are analyzed to find a setting adjustment for these process factors that provides a very low force for the metal forming process. For this investigation an orthogonal array L18 with three-fold replication is used. To find the optimum of the process, the experimental results are analyzed in accordance with the robust-design-method according to Taguchi (Liesegang et. al., 1990). For this purpose, so-called Signal-to-Noise-ratios are calculated. The analysis of variance for this S/N-ratios leads to a mathematical model for the deep drawing process. This model allows to find the pressumed optimal settings of the investigated factors. In the following, a confirmation experiment is carried out by using these optimal settings. The maximum drawing force of the confirmation experiment does not correspond with the confidence interval, which was calculated by analysis of variance techniques. So the predicted optimum of the process does not lead to a metal forming process with very low deep drawing force. The comparison with a full factorial plan shows that there are interactions between the investigated factors. These interactions could not be discovered by the used orthogonal array. Thus the established mathematical model does not describe the relation between the factors and deep drawing force in accordance with the practical deep drawing conditions.

Deformation Law of Cold Drawing Process of High Strength Bridge Cable Steel

2021 ◽  
Vol 1035 ◽  
pp. 801-807
Author(s):  
Xiao Lei Yin ◽  
Jian Cheng ◽  
Gang Zhao
Keyword(s):  
Strain Path ◽  
High Strength ◽  
Cold Drawing ◽  
Wire Drawing ◽  
Radial Deformation ◽  
Steel Bridge ◽  
Drawing Process ◽  
Single Pass ◽  
Potential Relationship ◽  
The Wire

High-strength cable-steel bridge is the “lifeline” of steel structure bridges, which requires high comprehensive mechanical properties, and cold-drawing is the most important process to produce high-strength cable-steel bridge. Therefore, through the ABAQUS platform, a bridge wire drawing model was established, and the simulation analysis on the process of stress strain law and strain path trends for high-strength bridge steel wire from Φ 12.65 mm by seven cold-drawing to Φ 6.90 mm was conducted. The simulation results show that the wire drawing the heart of the main axial deformation, surface and sub-surface of the main axial and radial deformation occurred, with the increase in the number of drawing the road, the overall deformation of the wire was also more obvious non-uniformity. In the single-pass drawing process, the change in the potential relationship of each layer of material was small, and multiple inflection points appeared in the strain path diagram; the change in the seven-pass potential relationship was more drastic, which can basically be regarded as a simple superposition of multiple single-pass pulls.

A Simple Analogous Model for the Determination of Cyclic Plasticity Parameters of Thin Wires to Model Wire Drawing

2007 ◽  
Vol 129 (3) ◽  
pp. 488-495
Author(s):  
T. Schenk ◽  
T. Seifert ◽  
H. Brehm
Keyword(s):  
Tensile Tests ◽  
Wire Drawing ◽  
Cyclic Stress ◽  
Cyclic Plasticity ◽  
Integration Time ◽  
Model Parameters ◽  
Compression Tests ◽  
Thin Wires ◽  
Fe Simulations ◽  
Analogous Model

Cyclic stress-strain measurements have to be performed in order to determine the cyclic plasticity parameters of material models describing the Bauschinger effect. For thin wires, the performance of tensile tests is often not possible due to necking of the specimen on exceeding the yield stress, whereas compression tests are uncritical. This paper presents an approach to determine the cyclic plasticity parameters by performance of compression tests for wires before and after drawing. Here, a simple analogous model is used instead of finite-element (FE) simulations. This approach has been applied for two different integration time steps in order to evaluate their influence on the fit and the accuracy of the integration. It is shown that good accuracy can be obtained for the cyclic plasticity parameters. For FE simulations using larger integration time steps, large deviations have been noted. However, there the analogous model could also be adopted in order to find appropriate model parameters. In general, it is the intention of this paper to show that searching an analogous model can be a very time- and cost-saving task.

scholarly journals Influence of a modified drawing process on the resulting residual stress state of cold drawn wire

2018 ◽  
Vol 190 ◽  
pp. 04004
Author(s):  
Markus Baumann ◽  
Alexander Graf ◽  
René Selbmann ◽  
Katrin Brömmelhoff ◽  
Verena Kräusel ◽  
...  
Keyword(s):  
Residual Stress ◽  
Residual Stresses ◽  
Wire Drawing ◽  
Industrial Applications ◽  
Drawing Process ◽  
Die Geometry ◽  
Residual Stress State ◽  
Drawing Die ◽  
Process Modification ◽  
The Wire

Torsion bars are used in automotive engineering as well as in other industrial applications. Such elements are produced by bending cold drawn wires. In conventional drawing processes tensile residual stresses occur near the surface of the wire. Small bending radii, which are required in limited assembly spaces, result in component failure due to reduced formability. Additional operations such as heat treatment or shot peening are necessary to influence the residual stress of the wire and to improve the dynamic stability of the torsion bar. The aim of the research is to reduce tensile residual stresses near the surface of the wire in order to eliminate process steps and to enhance formability. Therefore, a forming technology is developed by using a modified drawing die geometry on the basis of gradation extrusion. Finite element simulation is used to investigate the influences of element geometry, number of elements and process modification on the resulting residual stresses after wire drawing of a steel alloy. The results are evaluated and compared with the conventional wire drawing process. Furthermore, the requirements for the design of an experimental test device will be outlined as well as the measurement of the residual stresses by using X-ray diffraction.

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