Springback Assessment and Compensation of Tailor Welded Blanks

Description

Focusing on techniques developed to evaluate the forming behaviour of tailor welded blanks (TWBs) in sheet metal manufacturing, this edited collection details compensation methods suited to mitigating the effects of springback. Making use of case studies and in-depth accounts of industry experience, this book gives a comprehensive overview of springback and provides essential solutions necessary to modern-day automotive engineers. Sheet metal forming is a major process within the automotive industry, with advancement of the technology including utilization of non-uniform sheet metal in order to produce light or strengthened body structures. This is critical in the reduction of vehicle weight in order to match increased consumer demand for better driving performance and improved fuel efficiency. Additionally, increasingly stringent international regulations regarding exhaust emissions require manufacturers to seek to lighten vehicles as much as possible. To aid engineers in optimizing lightweight designs, this comprehensive book covers topics by a variety of industry experts, including compensation by annealing, low-power welding, punch profile radius and tool-integrated springback measuring systems. It ends by looking at the future trends within the industry and the potential for further innovation within the field. This work will benefit car manufacturers and stamping plants that face springback issues within their production, particularly in the implementation of TWB production into existing facilities. It will also be of interest to students and researchers in automotive and aerospace engineering. Cover Half Title Title Page Copyright Page Table of Contents Preface Editors Contributors Chapter 1 Weight Reduction Strategies in Passenger Car Manufacturing: Current Trends and Prospects 1.1 Introduction 1.2 Historical Passenger Car Weight and Fuel Economy Trend in the U.S 1.3 Impact of Weight on Fuel Consumption and CO[sub(2)] Emission 1.4 Weight Reduction Strategies 1.4.1 Design Optimization by Numerical Simulation 1.4.2 Material Alternative 1.4.3 Technological Innovation 1.4.3.1 Tailored Blanks 1.5 Conclusion and Future Works Acknowledgement References Chapter 2 Measurement and Compensation of Springback – A Comprehensive Review 2.1 Introduction 2.2 Types of Bending in Springback Problem Analysis 2.2.1 V-Bending 2.2.2 U-Bending 2.2.3 Draw Bending 2.2.4 Straight Flanging 2.2.5 Stretch Bending 2.2.6 Split-Ring Test 2.3 Definition of Springback 2.3.1 Springback versus Spring-go 2.3.2 Types of Springback 2.3.2.1 Wall Springback 2.3.2.2 Twist Springback 2.3.2.3 Flange Springback 2.3.3 Measurement of Springback 2.3.4 Factors That Affect the Springback 2.3.4.1 Material Properties 2.3.4.2 Thickness 2.3.4.3 Temperature 2.3.4.4 Friction 2.3.4.5 Blank Holder Force 2.3.4.6 Die and Punch Geometry 2.3.5 Measurement Tools 2.3.6 Compensation Strategies 2.3.6.1 Methods and Tools 2.3.7 Conclusions and Recommendations for Future Studies Acknowledgements References Chapter 3 Springback of Aluminium and Steel Joint by Friction Stir Welding – A Review 3.1 Introduction 3.2 Factors Affecting Springback 3.3 Springback Compensation 3.4 FSW of Al-Steel 3.5 Difficulty in Al-Steel FSW 3.6 Optimum Parameters 3.6.1 FSW Tool 3.6.2 Welding Parameters 3.6.3 Joint Configuration 3.6.4 Material Placement 3.7 Post-Forming Evaluation 3.7.1 Bending Test 3.7.2 Twist Forming 3.7.3 Limiting Dome Height Test 3.8 Springback in FSW of Al-Steel 3.8.1 Factors Affecting Springback in Al-Steel FSW 3.8.2 Compensation 3.8.3 FE Simulation 3.8.4 Model Use in the Simulation 3.8.5 Optimization 3.9 Conclusions Acknowledgement References Chapter 4 Overview and Issues Related to Geometrical Accuracy in the Single-Point Incremental Forming (SPIF) Process of Tailor Welded Blanks 4.1 Introduction 4.1.1 SPIF Limitations 4.1.2 Geometrical Accuracy and Dimensional Variation in SPIF 4.1.3 Parameters Affecting the Geometrical Accuracy 4.2 Effect of Process Parameters 4.2.1 Tool Diameters 4.2.2 Toolpath and Toolpath Strategies 4.2.2.1 Feed Rate 4.2.2.2 Compensation Methods 4.3 SPIF Development Variations 4.3.1 Double-Side Incremental Forming 4.3.2 Hybrid SPIF 4.4 Multi-Stage Strategies 4.5 Toolpath Optimization 4.6 Other Strategies 4.6.1 SPIF Process of Tailor Welded Blanks 4.6.2 Conclusions and Recommendation for Future Research Acknowledgement References Chapter 5 Springback in Tailor Welded Blanks Using a Heuristic Approach 5.1 Introduction 5.1.1 Tailor Welded Blanks 5.1.2 Formability of TWB 5.1.3 Springback in TWBs 5.1.4 Practical Methods to Control Springback 5.1.4.1 Restrike Method 5.1.4.2 Design Modifications of Tooling 5.1.4.3 Adjusting Forming Severities 5.1.4.4 Using Advanced Machine Tools 5.2 Springback Control in TWB Forming 5.2.1 Blank Holder Force and Tool Design Modification 5.2.2 Mathematical Modelling of Springback 5.3 Data-Driven Evolutionary Modelling 5.3.1 The EvoNN Algorithm 5.3.2 U-Bending of TWB: A Case Study 5.3.2.1 Setup Description and Springback Measurement 5.3.2.2 FE Modelling and Springback Prediction 5.3.2.3 Variable BHF Method to Control Springback 5.3.3 Predator-Prey EvoNN GA 5.3.3.1 Objective and Constraint Functions 5.3.3.2 Metamodel Construction and Optimization 5.4 Results and Discussion 5.4.1 Influence of Uniform BHF 5.4.2 Obtaining the Feasible Region 5.4.3 Pareto Frontier 5.5 Summary Notes References Chapter 6 Investigation of Twist Springback Pattern of the AA6061 Strip 6.1 Introduction 6.2 Literature Review 6.3 Methodology 6.4 Finite Element Modelling (FEM) 6.5 Specimen Profiles 6.6 Material Data 6.7 Validation 6.8 Twist-Forming Parameters 6.9 Specimen Preparation 6.10 Torsion Test Machine Setup 6.11 Twist Springback Measurement 6.12 Flat Profile 6.13 Tapered Profile 6.14 Results and Discussion 6.15 Effects of Twist Angle 6.16 Effects of the Thickness Ratio 6.17 Validation 6.18 Conclusions Acknowledgement References Chapter 7 Springback Study of Non-Uniform Thickness Aluminium Blanks 7.1 Research Background 7.1.1 Problem Statement 7.1.2 Scope of Study 7.2 Methodology 7.2.1 Optimization of Springback Parameters Using the Taguchi Method 7.2.1.1 Springback Parameters 7.2.2 Materials 7.2.3 Specimen Preparations 7.2.4 Sample Preparation 7.2.5 Experimental Setup 7.2.5.1 V-Bending Experiment 7.2.6 Springback Measurement 7.2.6.1 After-Unloading Measurement 7.2.6.2 Before Unloading Measurement 7.3 Results and Discussion 7.3.1 V-Bending Experiment 7.3.2 Strain Hardening 7.4 Conclusions References Chapter 8 Evaluation of Dissimilar Grade Aluminium Alloy-Tailored Blanks Fabricated by FSW 8.1 Introduction 8.2 Methodology 8.3 Results and Discussion 8.3.1 Load Pattern 8.3.2 Springback Pattern 8.3.2.1 Effect of Rolling Direction of Similar and Dissimilar Alloys 8.3.2.2 Effect of Retreating and Advancing Sides of Dissimilar Alloy 8.3.2.3 Effect of Bending Location of Similar Alloys 8.4 Conclusions and Future Work Acknowledgement References Chapter 9 Springback Simulation of Tailor Welded Blank and The Compensation by Using Displacement Adjustment and Spring Forward Methods 9.1 Introduction 9.2 Tailor Welded Blanks 9.3 Aluminium TWBs 9.4 TWB Numerical Simulation 9.5 Patchwork Blanks 9.6 Tailor-Rolled Blanks 9.7 Displacement Adjustment 9.8 Spring-Forward Method 9.9 Methodology 9.10 Finite Element (FE) Analysis of Tailored Blank 9.11 Springback Simulation 9.12 Results and Discussion 9.13 Conclusions References Chapter 10 Springback Study of Aluminium and Steel Joint TWBs by FE Analysis 10.1 Introduction 10.2 Simulation Model 10.3 Springback Simulation Using ANSYS 10.3.1 Springback Simulation for Joints with a Thickness of 1.5 mm 10.3.2 Springback Simulation for Joints with a Thickness of 2.1 mm 10.3.3 Springback Simulation for the Al-Steel Joint 10.4 Study on the Effect of the Puncher Offset to Springback 10.4.1 Effect of Puncher Offset to Springback for Plates with a Thickness of 1.5 mm 10.4.2 Effect of Puncher Offset on the Springback for Plates with a Thickness of 2.1 mm 10.4.3 Effect of Puncher Offset to Springback for Al-Steel Joint 10.5 Study of the Effect of Punch Stroke on Springbacks 10.5.1 Effect of Punch Stroke on Springback for Plates with a Thickness of 1.5 mm 10.5.2 Effect of Punch Stroke on the Springback for Plates with a Thickness of 2.1 mm 10.5.3 Effect of Punch Stroke on the Springback of Al-Steel Joint 10.6 Conclusions References Chapter 11 Effect of Post-Welding Heat Treatment on Springback Pattern of AA6061 TWBs 11.1 Introduction 11.2 Methodology 11.2.1 Selection of the Parameters and Their Levels 11.2.2 Materials and Equipment 11.2.3 Hardness Measurement 11.2.4 Experimental Setup 11.2.4.1 Springback Measurement 11.2.5 FE Simulation Model 11.2.6 Isotropic Hardening Springback Model 11.3 Results and Discussion 11.3.1 Experimental 11.3.2 FE Simulation 11.3.3 Comparison between Experimental and Simulation Results 11.4 Conclusions and Future Works References Chapter 12 Springback Analysis of Low-Power Laser Welded Aluminum Tailor Welded Blanks 12.1 Introduction 12.1.1 Methods for Determining Springback 12.1.2 Recent Studies on Springback of Aluminium TWBs 12.2 Methodology 12.2.1 Sample Preparations 12.3 Results and Discussion 12.3.1 Springback of Base Materials 12.3.2 Springback of Aluminium TWB Specimens 12.4 Conclusion References Chapter 13 Recent Studies and Related Issues in Tailor Blanks – A Short Review 13.1 Introduction 13.2 Recent Fabrication Methods 13.3 Recent Application of Tailored Blanks 13.4 Formability 13.5 Sustainability Issue in Tailored Blanks 13.6 Conclusions References Index