Design Optimization of Roller Straightening Process for Steel Cord Using Response Surface Methodology

Design Optimization of Roller Straightening Process for Steel Cord using Response Surface Methodology

Jong-Sup Lee, Hoon Huh, Jong-Gu Bae, Jun-Wu Lee and Deuk-Tae Kim

Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology, 373-1, Science Town, Daejeon, 305-701, Korea

R&D center, KISWIRE, 533, Nam-Gu, Pohang, Kyungbuk, 790-840, Korea

Abstract. A roller straightening process is a metal forming technique to improve the geometric quality of products such as straightness and flatness. The geometrical quality can be enhanced by eliminating unnecessary deformations produced during upstream manufacturing processes and minimizing any detrimental internal stress during the roller straightening process. The quality of steel cords can be achieved by the roller straightening depends the process parameters. Such process parameters are the roll intermesh, the roll pitch, the diameter of rolls, the number of rolls and the applied tension. This paper is concerned with the design optimization of the roller straightening process for steel cords with the aid of elasto-plastic finite element analysis. Effects of the process parameters on the straightness of the steel cord are investigated by the finite element analysis. Based on the analysis results, the optimization of the roller straightening process is performed by the response surface method. The roller straightening process using optimum design parameters is carried out in order to confirm the quality of the final products.

Keywords: optimization, roller straightening process, steel cord, response surface methodology, finite element analysis PACS:47.11.fg

INTRODUCTION

One of the most important problems in the production of steel cords is assurance of straightness that is the basis for the successful manufacturing of final products since the straightness of the steel cord has a major contribution to the quality of final products. During the manufacturing process, the steel cord experiences severe plastic deformation. The un-uniformly distributed plastic strain at the cross section of the wire makes the wire bent and deflected. On the other hand, the tensile residual stress at the outside of the wire along the longitudinal direction due to the drawing process has very detrimental effect on the fatigue life of wire products[l].

A roller straightening process is a metal forming technique to improve the geometric quality of products such as straightness and flatness. To reduce or remove the undesired the residual stress and plastic strain, the roller straightening process is indispensable for the production of the straight steel cord. During the roller straightening process, the wire is bended repeatedly and the outside of the wire is slightly stretched. This stretching of wire reduces the tensile residual stress around the outside of the wire and makes the wire straight[2].

The quality of steel cords can be achieved by the roller straightening depends the process parameters[3]. Such process parameters are the roll intermesh, the roll pitch, the diameter of rolls, the number of rolls and the applied tension[4-5]. It is well known that the design of an effective roller straightener becomes more difficult and nearly impossible by experience-based methodology as the strength of the material increases. It is indispensable to determine the process parameters systemically using successive simulations based on the optimization techniques such as the response surface method or the Taguchi method[6].

This paper is concerned with the design optimization of the roller straightening process for steel cords with the aid of elasto-plastic finite element analysis. Effects of the process parameters on the straightness of the steel cord are investigated by the finite element analysis. Based on the parameter study, the optimization of the roller straightening process is performed by the response surface method. Finally, the roller straightening process using optimum design parameters is carried out in order to confirm the quality of the final products.

CP908, NUMIFORM '07, Materials Processing and Design: Modeling, Simulation and Applications edited by J. M. A. Cesar de Sa and A. D. Santos

2007 American Institute of Physics 978-0-7354-0415-1/07/S23.00

581

FIGURE 1. Cross sectional view of finite element model of the wire

FIGURE 2. Schematic diagram of the roller straightener and the wire

PARAMETER STUDY OF ROLLER STRIGHTENING PROCESS

The general process parameters of the roller straightening process are the roll intermesh, the roll pitch, the diameter of rolls, the number of rolls and the applied tension. Also, there is additional parameter such as groove shape of rolls and which has some effects on the geometric quality of the wire. In this study, the response surface methodology is used for the optimization of the roller straightening process. To construct the response surface of the process, finite element simulations for obtaining the response at the each design points should be performed. In general, the number of finite element analysis required for constructing the RSM increases as the number of design variables increases. It is almost impossible to optimize the roller straightening process considering the all process parameters. Prior to the optimization stage, it is necessary to investigate the effects of the process parameters on the geometrical quality of the wire and to exclude the process parameters which have very small effects from the design variables of the optimization for an efficient design process. It is easily to expect that decreasing the number of rolls keeping the quality of wire will improve efficiency of the roller straightener especially the fatigue life of rolls.

In this study, the roller straightener with 11 rollers is considered and number of rolls is not changed. Among the process parameters, the roll intermesh,

1

Stre

ow

1L

4200 -,

4000-

3800-

3600-

3400-

3200-

3000-

2800-

_^ .-

2600-

0.000 0.002 0.004

M1: a =2778.5 MPa M2: a =2974.7 MPa

y M3: a =3276.4 MPa M4: a =3410.8 MPa

y

0.006 0.008 0.0

Plastic Strain

FIGURE 3. This is the Style for Figure Captions. Center this if it doesn't run for more than one line

the roll pitch, the diameter of rolls and applied tension are selected for the parameter study.

Finite element analysis of roller straightening process

For the parameter study of the roller straightening process, finite element analyses of the roller straightening process are carried out using a commercial implicit finite element code, ABAQUS/Standard. Fig. 1 and Fig. 2 show the cross sectional view of the finite element model for the analysis and the schematic diagram of the roller straightener and the wire respectively. Only half of wire is considered utilizing the symmetry. The diameter of wire is 0.30 mm and the length of finite element model for the wire is 38mm. In the real roller straightening process, the wire passes the roller straightener continuously and the length of wire is much higher than 38 mm. Since the diameter of wire is very small compared with the length of wire, extremely large number of finite elements are required to model the wire. In this study, only 38mm of wire is considered and the equivalent boundary conditions are imposed on the front and end of wire to reduce computational time. For the finite element analysis, wires with different carbon contents and area reduction ratios are used. Table 1 shows the conditions and Fig. 3 denotes the flow stress curves of the wires which are applied to the finite element analysis.

TABLE 1. conditions of 4 wire materials wire

material

Ml M2 M3 M4

carbon contents [wt %]

0.8 0.9 0.8 0.9

area reduction ratio [%]

96.85 96.85 97.56 97.56

yield stress [MPa] 2778.5 2974.7 3276.4 3410.8

582

4.0

3.5

r - 2.5

_. 2.0

I " i 10

0.5

0.0

" - - - M 1 - - i - M 2

- - M 3 - - T - M 4

-

/Cyi _==X X X

0.5 1.0 1.5 2.0 2.5 Intermesh [mm]

3.0

FIGURE 4. maximum stress along the longitudinal direction with respect to the intermesh

o

0.025

0.020

0.015

0.010

0.005

0.000

-M1,1=1.5mm M2,1=1.5mm M3,1=1.5mm M4, l=3.0mm

200 400 600 800 Applied tension [MPa]

1000

FIGURE 6. maximum stress along the longitudinal direction with respect to the applied tension

0.0025

0.0020

0.0015

0.0010

0.0005

0.0000 1.0 1.5 2.0 2.5

Intermesh [mm]

FIGURE 5. maximum plastic strain along the longitudinal direction with respect to the intermesh

Young's modulus of the wire is 210GPa and the rolls are modeled by the analytic rigid surface option of ABAQUS/standard. The friction between the wire and rolls is neglected and the rotational degrees of freedom of rolls are removed.

Results of parameter study

The process parameters which are estimated in this study are the diameter of rolls, roll pith, intermesh of rolls and applied tension. The reference design of roller straightener is diameter of 8mm, pitch of 19 mm, intermesh of 1.5 mm and applied tension of 150MPa.

At first, the effect of the intermesh of rolls is investigated and the intermesh of rolls is change from 0.5 mm to 3.0mm. Fig. 4 and Fig. 5 show the maximum stress and the maximum plastic strain along longitudinal direction of the wire as a function of the intermesh with respect to the material of wire during the roller straightening process.

4.25

4.00

=; 3.75

^ 3.50

85 3 | 2.75

0.25

0.00

"

-

A~^^

-""^

"

i

^^^\M^^^

^ m -

_______ -T ^^v

M1,1=1.5mm AM2,1=1.5mm M3,1=1.5mm M4, l=3.0mm

200 400 600 800 Applied tension [MPa]

1000

FIGURE 7. maximum plastic strain along the longitudinal direction with respect to the applied tension

From the graphs, it is easily known that as the intermesh increases, the stress and plastic strain also increase and the stress and plastic strain do not increase any more above some intermesh. It is because the curvature of wire during bending deformation determines the maximum stress at the outside of the wire and the curvature radius of the wire can not be smaller than the radius of the roller.

Secondly, while the applied tension is changed from 200MPa to lOOOMPa with interval of 200MPa, finite element analyses are carried out to estimate the effect of the applied tension on the straightening quality. Fig. 6 and Fig. 7 show the maximum stress and the maximum plastic strain along longitudinal direction of the wire as a function of the applied tension with respect to the material of wire during the roller straightening process. As expected, increase of the applied tension leads the higher maximum residual stress and plastic strain.

Finally, the influences of the roller pitch and roller radius are investigated.

583

4.0

3.5

I " & 2.5 -%

FIGURE 11. moment and stress of wire along longitudinal direction

To accomplish this purpose, the sum of moment of wire should be minimized or removed by the third, forth and fifth upper rollers. Fig. 11 shows the schematic diagram of wire. The constructed objective function and constraint as follows:

minimize

s.t.

ize

before roller straightening after roller straightening

t -Qt

(c) FIGURE 13. response surfaces and contour plots: a) I3=0.85957; b) I4=0.80322; c)I5=0.80608; Fig. 13 show the response surface and contour plots. Since there are three design variable, one of design variable is fixed at the optimum value. I5 is most important and effective variables among the three intermesh of rollers.

To confirm the leveling effect of optimum design, the finite element analysis of the roller straightening process with wire which has un-uniform longitudinal stress distribution initially. In general, the cold-drawn wire has tensile residual stress along longitudinal direction of wire[8]. Fig. 14 shows the variation of residual stresses of wire after the roller straightening process with optimum design values. The optimum design can reduce the residual stress of wire remarkably.

CONCLUSION

In this study, the influences of process parameter of roller straightening are investigated by finite element

Residual stress along longitudinal direction [GPa]

FIGURE 14. comparison of residual stress of wire between before roller straightening and after roller straightening

analyses of the roller straightening process. The investigations made following conclusions: - As increase of the intermesh and the applied tension, the maximum stress of wire during the process also increases. -the maximum stress is determined by the roller radius and the applied tension.

The optimization of the roller straightening process using response surface methodology with aid of finite element analysis is performed. The intermeshes of each rollers are selected as design variables. The most dominant variable is the intermesh of the last rollers. The optimum design can reduce the residual stress of wire remarkably and make the bent wire straight.

REFERENCES

1. M. Elices, "Influence of residual stresses in performance of cold-drawn pearlitic wires", Journal of Materials Science, 39, 3889-3899 (2004)

2. E. Albert and M. Schilling, "Quality improvements during wire processing", Wire, 49, 1/98, 44-46 (1998)

3. M. Paech, "Factors relating to the wire straightening process: process and peripherals", Wire journal international, 35, 12, 64-68 (2002)

4. H. Schneidereit and M. Schilling, "Determination of the minimum number of rollers on wire straightening units", Wire, 47, 5, 318-320(1996)

5. N. K. D. Talukder and W. Johnson, "On the arrangement of rolls in cross-roll straighteners", InternationalJournal of Mechanical Science, 23,213-220 (1981).

6. H. Huh, J. H. Heo and H. W. Lee, "Optimization of a roller levelling process for A17001T9 pipes with finite element analysis and Taguchi method", International journal of machine tools & manufacture, 43, 4, 345-350 (2003)

7. HyperStudy 7.0 User's Manual, Altair Engineering. 8. J. M. Atienza et al., "Residual stresses in cold drawn

ferritic rods", ScriptaMaterialia, 52, 305-309 (2005)

586

Welcome ScreenTitle PageProceedingsISBN/Copyright InformationPrefaceOrganizationContentsPART IPLANARY LECTURESConstitutive Descriptions for Metal Forming SimulationsThree-dimensional Modeling of Void Growth in Friction Stir Welding of Stainless SteelComputational Modelling of a Thermoforming Process for Thermoplastic StarchComputational Strategies for Polymer Coated Steel Sheet Forming SimulationsConvection of Local Level Set Function for Moving Surfaces and Interfaces in Forming FlowThe Role of a General Purpose Code in Forming Simulations

MINI SYMPOSIAPREDICTION OF NECKING AND FRACTURE IN METAL SHEETSPredictions of Necking with Analytical Criteria and Comparisons with Experimental ResultsInfluence of the Plastic Material Behaviour on the Prediction of Forming LimitsOn Necking, Fracture and Localization of Plastic Flow in Austenitic Stainless Steel SheetsPossibilities and Influencing Parameters for the Early Detection of Sheet Metal Failure in Press Shop OperationsDamage Prediction in Sheet Metal FormingModelling of Local Necking and Fracture in Aluminium AlloysFormability Prediction of Aluminum Sheet in Automotive ApplicationsSEM-EBSD Based Realistic Modeling and Crystallographic Homogenization FE Analyses of LDH Formability TestsOn the Prediction of Plastic Instability in Metal SheetsPrediction of Ductile Failure in the Stretch-Forming of AA2024 SheetsForming Limit Predictions for the Serrated Strain Paths in Single Point Incremental Sheet FormingAbout the Neglected Influence of Gradients on Strain LocalisationPrediction of Formability in Sheet Metal Forming Processes Using a Local Damage ModelAnisotropy and Formability in Sheet Metal FormingCrachFEMA Comprehensive Approach for the Prediction of Sheet Metal FailureIncreasing the Robustness of the Sheet Metal Forming Simulation by the Prediction of the Forming Limit Band

RECENT DEVELOPMENTS IN FORMING PROCESSESA General Arbitrary Lagrangian Eulerian Formulation for the Numerical Simulation of 3D Forming ProcessesError Estimation and Accurate Mapping Based ALE Formulation for 3D Simulation of Friction Stir WeldingNumerical Modelling of Metal Flow in the Cold Forming of Industrial FastenersFinite Element Simulation of Plastic Joining Processes of Steel and Aluminum Alloy SheetsMeshless Simulation of Friction Stir WeldingFrom Steady-State to Cyclic Metal Forming ProcessesDevelopment of Multi-Scale Finite Element Analysis Codes for High Formability Sheet Metal GenerationMulti Scale Modeling of Phenomena Caused by Changes of the Deformation Path in Materials FormingFinite Element Prediction of Sheet Forming Defects Using Elastic-Plastic, Damage and Localization ModelsAnisotropic Volume Mesh Generation Controlled by Adaptive Metric SpaceImproved Contact Algorithms for Implicit FE Simulation of Sheet FormingFailure Prediction in Forming ProcessesMilling Process FEM Simulation for Identification of Material Parameters Directly from Experiments3D FEM Simulation of the Flow Forming Process Using Lagrangian and ALE MethodsOptimum Structural Topology and Shape Design Using Three Phase Hybrid GA and Artificial Density MethodCimlib: A Fully Parallel Application for Numerical Simulations Based on Components AssemblyDesign Optimization for Three-dimensional Extrusion ProcessesNumerical Forming Simulations and Optimisation in Advanced Materials

NUMERICAL SIMULATION OF POLYMER PROCESSINGAdvanced Multiscale Modelling of Composite Welding ProcessesIntegrated Simulation of an Aspheric Lens Combining Injection Moulding Analysis with Ray TracingThree-dimensional Numerical Simulation of Segregation in Dense SuspensionsA New Approach for the Validation of Filling Simulations in Micro Injection MouldingNumerical Simulation of the Flow Behavior and Breakthrough Phenomenon in Co-injection MoldingFluid Structure Interaction Techniques for Extrusion and Mixing ProcessesAn Accurate Simulation of Thermoforming and Blow-molding Processes Using the Space Fiber Rotation (SFR) ConceptThe Use of Elasto-visco-plastic Material Model Coupled with Pressure-volume Thermodynamic Relationship to Simulate the Stretch Blow Molding of Polyethylene TerephthalateSimulation of the Cooling of a Semi-Crystalline Polymer in the Injection Molding Process Including PVT BehaviorRheology of Suspensions Derived from Numerical SimulationNumerical Modeling of the Deformation in Polymer Blends under Shear FlowInjection Molding Simulation: Taking into Account the Process History to Predict the Anisotropy in the End-use PropertiesTwo-Phase Model of Liquid-Liquid Interactions with Interface Capturing: Application to Water Assisted Injection Molding

NUMERICAL REPRESENTATIONS OF MICROSTRUCTURES AND MODELING OF THEIR EVOLUTIONSFull-field Model and Experimental Validation of Subgrain Texture and Microstructure Evolution of Polycrystalline CopperDevelopment of Numerical Tools for the Multiscale Modelling of Recrystallization in Metals, Based on a Digital Material FrameworkCrystal-plasticity-based FE Modelling of a Dual-phase Microstructure in Which Grains Have Non-Uniform Shape and SizeReducing Computational Cost and Allowing Automatic Remeshing in FEM Models of Metal Forming Coupled with Polycrystal PlasticityModeling of 3D Aluminum Polycrystals during Large DeformationsStudy of Axes Rotation during Simple Shear Tests on Aluminum Sheets

DESIGN AND OPTIMIZATION OF FORMING PROCESSESRobust Design of Parameters Fluctuations Based on Finite Element Method and Orthogonal Array in Springback3D Simulation and Validation of Tube Piercing Process3D FEM Geometry and Material Flow Optimization of Porthole-die ExtrusionNumerical Prediction of Elastic Springback in an Automotive Complex Structural PartMeasuring of Geometrical Precision of Some Parts Obtained by Asymmetric Incremental Forming Process after TrimmingNumerical Design of Experiments to Analyse the Contact Conditions in MicroformingOn the Determination of the Blank Shape Contour for Thin Precision Parts Obtained by StampingTopology Optimization of a Stamping DieResponse Surface Method for the Rapid Design of Process Parameters in Tube HydroformingSensitivity Analysis and Optimization of Tube Bending Coupled with Pressure TestOptimization of Forming Processes with Different Sheet Metal Alloys

OPTIMIZATION AND ROBUSTNESS IN FORMINGGradient, Non-Gradient and Hybrid Algorithms for Optimizing 3D Forging Sequences with UncertaintiesA Study for Efficiently Solving Optimisation Problems with an Increasing Number of Design Variables3D Die Shape Optimization Using Direct Compensation and Surface ApproximationA Robust Optimisation Strategy for Metal Forming ProcessesA Simplified Methodology for Estimating the Variance of Material Properties, in FE Analysis under Uncertainty of Sheet and Tube Metal Forming Processes

TOOLS OPTIMISATION IN FORMING PROCESSESA Fully Coupled Simulation and Optimization Scheme for the Design of 3D Powder Injection Molding ProcessesImplementation of the Artificial Neural Networks to Control the Springback of Metal SheetsSimulation of the Two Stages Stretch-Blow Molding Process: Infrared Heating and Blowing ModelingCooling Channel Optimization for Injection MoldingGeometrical Optimization in Clinch Forming Process Using the Response Surface MethodOptimizations of Coat-Hanger Die, Using Constraint Optimization Algorithm and Taguchi Method

FORMING PROCESSES OF MAGNESIUM ALLOYS AND THEIR COMPUTER SIMULATIONApplications of Computer Simulation Methods in Plastic Forming Technologies for Magnesium AlloysFinite Element Simulation of Magnesium AZ31 Alloy Sheet in Warm HydroformingStudy on Numerical Simulation and Experiment of Fabrication Magnesium Semisolid Slurry by Damper Cooling Tube MethodWarm Deep Drawing of Rectangular Parts of AZ31 Magnesium Alloy Sheet Adopting Variable Blank Holder ForceNumerical Modeling of Magnesium Alloy Sheet Metal Forming at Elevated TemperatureWarm Deep Drawing of Rectangular Cups with Magnesium Alloy AZ31 SheetsDesign Optimization of Roller Straightening Process for Steel Cord Using Response Surface Methodology

CONSTITUTIVE MODELING AND MECHANICS FOR METAL FORMINGEvaluation of Flow Stresses of Tubular Materials Considering Material/s AnisotropyOn the Adequate Representation of Velocity Fields in a Narrow Layer Near Maximum Friction SurfacesStudy of Titanium Alloy Sheet during H-Sectioned Rolling Forming Using the Taguchi MethodOn Using Homogeneous Polynomials to Design Anisotropic Yield Functions with Tension/Compression Symmetry/AssymetryAsymmetric Rolling Process Simulations by Dynamic Explicit Crystallographic Homogenized Finite Element MethodCompressive Instability Phenomena during SpringbackComparison of Two Commercial FE-Codes for Sheet Metal FormingA New Modelling of Blanking for Thin Sheet in Copper Alloys with Dynamic RecrystallizationFlow Stress Curves Using New Volume Measurement Method for Hydraulic Bulge TestFinite Element Simulation of Sheet Metal Forming Using Anisotropic Strain-Rate PotentialsStudy on the Hemisphere Deep Drawing Process of Metal Sheet Based on the FEM SimulationModelling the Material Behaviour of Metastable Stainless SteelsModeling of Deformation of FCC Polycrystalline Aggregates Using a Dislocation-based Crystal Plasticity ModelConstitutive Modeling of Magnesium Alloy SheetsConvolute Cut-Edge Design for a Circular Cup Based on FEM and an Analytical ApproachMaterial Models to Study the Bauschinger Effect on an Aluminum Shear Test SpecimenEaring Prediction in Cup Drawing Based on Non-Associated Flow RuleKinematic Hardening: Characterization, Modeling and Impact on Springback Prediction

DEVELOPMENTS IN FINITE ELEMENT TECHNOLOGIES FOR FORMING PROCESSESAdaptive Through-thickness Integration Strategy for Shell ElementsTube Drawing Process Modelling by a Finite Element AnalysisMicro Wire-Drawing: Experiments and ModellingGurson/s Model: ALE Formulation and Strain LocalizationTowards Efficient Modelling of Macro and Micro Tool Deformations in Sheet Metal FormingFluid Structure Interaction Analysis in Manufacturing Metal/Polymer Macro-CompositesIntegrated Modelling of Damage and Fracture in Sheet Metal FormingAn Overview of Sheet Metal Forming Simulations with Enhanced Assumed Strain ElementsAnalysis of BCC Sheet Metal Forming by Polycrystalline Plasticity MethodA New Solid-Shell Finite Element Technology Incorporating Plastic Anisotropy in Forming SimulationsIntegration of Heat Transfer Coefficient in Glass Forming Modeling with Special Interface Element

PART IIGENERAL TOPICSSHEET FORMINGFinite Element Simulation of Sheet Metal Forming and Springback Using a Crystal Plasticity ApproachResidual Stress in Sheet Metal Parts Made by Incremental Forming ProcessSensitivity Analysis of Technological and Material Parameters in Roll FormingCrashworthiness of Aluminium Tubes; Part 1: Hydroforming at Different Corner-fill Radii and End Feeding LevelsCrashworthiness of Aluminium Tubes; Part 2: Improvement of Hydroforming Operation to Increase Absorption EnergyNumerical Prediction of Springback Shape of Severely Bent Sheet MetalSpringback Simulation of High Strength Steel Sheet Using Local Interpolation for Tool SurfacesA Study on Process Design Methods of Redrawing Square CupsResearch on the Effects of the Movable Die and Its Counter Force on Sheet HydroformingSlip Line Field Applied to Deep DrawingControl of Springback in Sheet Metal U-bending through Design ExperimentIncremental Volumetric Remapping Method: Analysis and Error EvaluationInfluence of Drawbeads in Deep-drawing of Plane-strain Channel Sections: Experimental and FE AnalysisStudy on the Influence of the Refinement of a 3-D Finite Element Mesh in Springback Evaluation of Plane-Strain Channel SectionsDeep Drawing Simulation of High and Ultrahigh Strength Steels under Consideration of Anisotropic HardeningError Analysis in Explicit Finite Element Analysis of Incremental Sheet FormingProcess Development and Simulation for Cold Fabrication of Doubly Curved Metal Plate by Using Line Array Roll SetThe Material Rolling Direction Influence on Springback Effect in Case of a U-shape Part Made from Tailor Welded StripesThe Effect of Temperature Rise in a Fine Blanking ToolExperimental Campaign Definition for Sheet Hydroforming through CAE Tools UsageExperimental and Numerical Investigations in Single Point Incremental Sheet FormingInvestigation of Forming Performance of Laminated Steel Sheets Using Finite Element AnalysesStudy the Effect of Curvature on Spring Back of Double Curved Steel Sheet Using New MethodFurther Experimental Verification of a Proposed Localized Necking CriterionSome Considerations in Modeling Axisymmetric Deep Drawing and Redrawing Process and LDR PredictionFETI-INDEED: New Perspectives in Metal Forming SimulationImpact of Elastic Modulus Degradation on Springback in Sheet Metal FormingA Study on Segmented Multiple-step Forming of Doubly Curved Thick Plate by Reconfigurable Multi-Punch DiesAdaptive Refinement Procedure for Sheet Metal FormingCorrelation of FEA Prediction and Experiments on Dual-phase Steel Automotive RailsComputationally Efficient Finite Element Analysis Method Incorporating Virtual Equivalent Projected Model for Metallic Sandwich Panels with Pyramidal Truss CoresSectional Finite Element Analysis on Viscous Pressure Forming of Sheet Metal

BULK FORMINGA Comparison between the Properties of Solid Cylinders and Tube Products in Multi-pass Hot Radial Forging Using Finite Element MethodPractice of Process Modeling of Metal Forming in Manufacturing EnvironmentA New Method for Reducing Dimensional Variability of Extruded Hollow SectionsAnalytic Model for Estimation of Cold Bulk Metal Forming SimulationsProcess Modelling of IN718 for Free ForgingEffect of Flaw Removal on Billets in RollingInvestigations on Forging Dies with Ceramic Inserts by Means of Finite-element AnalysisThe Relevance of the Preform Design in Coining Processes of Cupronickel AlloyAnalysis of Axisymmetrical Compression Processes by the Finite Element MethodElasto-plastic Simulation Concepts for Profile Transfer and Flatness Prediction in Flat Hot RollingNumerical Simulation of Damage during Forging with Superimposed Hydrostatic Pressure by Active MediaComputer Simulation of Material Flow in Warm-forming Bimetallic ComponentsFlash Design Optimization in Blade Forging Using FEM MethodOptimal Cluster Mill Pass Scheduling with an Accurate and Rapid New Strip Crown ModelUse of a TiBN Multilayer Coating for Wear Reduction

CASTING, MOLDING, QUENCHINGSimulation of an Aspheric Glass Lens Forming Behavior in Progressive GMP ProcessA Model for Prediction of Shrinkage Defects in Long and Short Freezing Range MaterialsApplication of Moldex3D for Thin-wall Injection Moulding SimulationNumerical Simulation of Horizontal Continuous Casting Process of C194 Copper AlloyModeling and Simulation of the Flow of a Thermoplastic Polymer during Filling of a Cylindrical Micro-Cavity

MATERIALS, JOINING, AND POWDER FORMINGDevelopment of the Fast FE Method for Welding DeformationStress-strain Analysis of Single-lap Tensile Loaded Adhesive JointsDevelopment of MetalOPolymer Mixtures Dedicated to Macro and Micro-powder Injection Moulding: Experiments and SimulationsThermo-mechanical Calculations of Hybrid Rotary Friction Welding at Equal Diameter Copper Bars and Effects of Essential Parameters on Dependent Special VariablesNumerical Simulation of Sintering Process in Ceramic Powder Injection Moulded ComponentsModelling and Simulation of Tensile Fracture in High Velocity Compacted Metal PowderNumerical Analysis of the Resistance to Shear Test of Clinched Assemblies of Thin Metal Sheets

MACHININGNew Modelling Strategies for Metal Cutting3D Simulation of Adiabatic Shear Bands in High Speed MachiningSome Considerations on the FE Simulation of Orthogonal Cutting Using Different Classes of Numerical CodesFE Thermal Modelling of Machining with Ball End MillingModelling of Tool Wear and Residual Stress during Machining of AISI H13 Tool SteelAnalytical Modelling of Milling for Tool Design and SelectionA Numerical Study of the Mechanical Behavior of Silicon Carbide due to Pressure-induced Phase Transformations during Nanoindentation

THERMAL MECHANICAL PROCESSINGWarm Hydroforming of Lightweight Metal SheetsSimulation and Evaluation of Phase Transformations and Mechanical Response in the Hot Stamping ProcessMesh Re-zoning in Multi-stand RollingAnalysis of Molding Process for Epoxy Resin Used for Electrical InsulatorSimulation and Experimental Results of the Hot Metal Gas Forming Technology for High Strength Steel and Stainless Steel Tubes FormingAnalysis of Deformation Behavior of Plastic during Lining on Steel Pipe with an FEM

METHODS FOR MATERIAL AND PROCESS DESIGNImpact of the Material Variability on the Stamping Process: Numerical and Analytical AnalysisOptimisation of Shape Parameters and Process Manufacturing for an Automotive Safety PartExperimental and Numerical Investigation of Forging Process to Reproduce a 3D Aluminium Foam Complex ShapeDetermination of Slitting Criterion Parameter during the Multi Slit Rolling ProcessApplication of Numerical Modelling to Ribbed Wire Rod Dimensions Precision IncreaseModelling of Rolling and Cooling Processes of the Bulb Bars HP220Statistical Tools and Artificial Intelligence Approaches to Predict Fracture in Bulk Forming ProcessesFatigue Life Prediction in Rapid Die CastingPreliminary Work in View of Current Research

MATERIAL CHARACTERIZATIONForming Limit Prediction of Metastable Materials with Temperature and Strain Induced Martensite TransformationPlastic Deformation Characteristics of AZ31 Magnesium Alloy Sheets at Elevated TemperatureExperimental and Numerical Study of the Thermomechanical Behavior of a Stamping OperationTube Bulge Process: Theoretical Analysis and Finite Element SimulationsEstimation of Rheological Law by Inverse Method from Flow and Temperature Measurements with an Extrusion Die

INELASTIC MATERIAL MODELSElastic-plastic Constitutive Equation of WC-Co Cemented Carbides with Anisotropic DamageFinite Stain Viscoelastic-plastic Deformation of Polymers Using Finite Element SimulationA Coupled Model of Flow Stress and Microstructure EvolutionOn the Modeling of Plastic Deformation of Magnesium AlloysA Flow Stress Formulation of Magnesium Alloy at Elevated TemperatureFinite Element Analysis of Polycrystalline Deformation with the Rate-dependent Crystal PlasticityAccurate Hardening Modeling as Basis for the Realistic Simulation of Sheet Forming Processes with Complex Strain-path ChangesA Mathematical Model for Plasticity and Cosmology

MULTI-SCALE MODELINGA Multiscale Model Based on Intragranular Microstructure: Influence of Grain-scale Substructure on Macroscopic Behaviour of an IF-Steel during Complex Load PathsForming Simulations of MMC Components by a Micromechanics Based Hierarchical FEM ApproachThree-dimensional Cellular Automata for Simulation of Microstructure Evolution during Recrystallization3D Modeling of SinteringCase of Two GrainsTwo-phase Multiscale FEM Modelling of Macrosegregation Formation in Steel SlabsThe FEM Simulation of Cementite Lamellas Deformation in Pearlitic Colony during Drawing of High Carbon SteelMultiscale Simulations of the Elastic Properties of Polycrystalline Silicon

DAMAGE EVOLUTION AND FAILUREDamage Evolution on Mechanical Parts Under Cyclic LoadingNumerical Simulation of Burst Defects in Cold Extrusion ProcessStress Limit Model with Deformation Dependent Damage for Failure Prediction in Bulk Forming ProcessesPrediction of the Fracture due to Mannesmann Effect in Tube PiercingEvaluation of Fracture in a Three Stage Forging Process Using Continuum Damage MechanicsA Finite Element Approach to Mechanical Degradation and Failure of Ductile MaterialsAging Damage Effects on Composite Structures

FORMABLITY AND FRACTUREEvaluation of Forming Limit by the 3 Dimensional Local Bifurcation TheoryFormability Analysis of Magnesium Alloy Sheet Bulging Using FE SimulationFailure Analysis With a New Tool Geometry, X-Die, in Areas with High Tension/Compression StrainsNumerical and Experimental Studies on Strain Distribution and Weld Line Movement in Stretch Forming of Tailor Welded BlanksFinite Element Modeling of Transition Zone in Friction Stir Welded Tailor-made BlanksNumerical and Experimental Investigations into Tailored Welded Blanks Formability

NUMERICAL METHODS AND APPLICATIONSDevelopment and Applications of Simulation System JSTAMP/NV for Tube Hydro-FormingNew Method to Evaluate and Compensate 3D-SpringbackSmoothed Particle Hydrodynamic Simulation of Iron Ore Pellets FlowModeling the Interaction Effects between Tools and the Work Piece for Metal Forming ProcessesAn eXtended Arbitrary Lagrangian-Eulerian Finite Element Model (X-ALE-FEM) in Large Plasticity DeformationsDecoupled Simulation Method for Incremental Sheet Metal FormingCoupling Finite Element and Meshless Methods to Deal with Contact and Friction in Forging ProcessesFinite Element Technology in Forming SimulationsTheoretical Aspects and Practical Applications of a New Solid-shell ElementIntegration of the Security Sub-modules Elements in the Automotive IndustryNumerical Simulations of Moving Interfaces by Level Set Method in the Partition of Unity ConceptPredicting Distributive and Dispersive Mixing in Polymer ExtrusionThe Use of DEM to Capture the Dynamics of the Flow of Solid Pellets in a Single Screw ExtruderLevel-Set Method Used to Track the Glass-air Interface in the Blow Step of Glass Containers3 Macroscopic Electromechanical Behavior of Polycrystalline Piezoelectric Materials BaTiO and PbTiO3; a 3D AnalysisNumerical Computation of the Heat Transfer Coefficient in the 2-D Inverse Design Stefan ProblemAdaptive Anisotropic Mesh Technique for Coupled Problems: Application to Welding SimulationIdentification of Constitutive Parameters Using Inverse Strategy Coupled to an ANN ModelImplementation of the eXtended Finite Element Method (X-FEM) in Frictional Contact ProblemsParallel 3D Mesh Generation Using Geometry DecompositionOn Scalability of Distributed Simulation and Optimization of Forming ProcessesIntegrated Forming Simulation Using State-of-the-Art MethodologiesThermal Conductivity of SWCNT Nanocomposites Determined Using Finite Element MethodFE Simulation of Dieless Drawing Process for Small-size Non-circular TubesA Nonconforming Multidomain Method for Contact ProblemsProblems of Numerical Modelling of Processes Determined by Shear FractureWarm Forming Simulation of Titanium Tailor-welded Blanks with Experimental Verification

Author IndexHelpSearchExit