Innovative Structural Materials: Reducing Weight of Transportation Equipment (Springer Series in Materials Science, 336)

This book is devoted to innovative structural materials for multi-materialization. It is based on results of a 10-year national project, The Innovative Structural Materials Research and Development Project, which was carried out in Japan, aimed at reducing the weight of materials (steel, aluminum alloys, magnesium alloys, titanium alloys, thermoplastic CFRP, carbon fiber) and components used in transportation equipment such as automobiles. In this project, collaborative research in a total of nine fields including materials, joining, and structural designing was also carried out in order to realize multi-materials. This book is compiled with the aim of handing down the technical and academic results obtained through these research and development activities to the next generation of researchers and students. This book enables material engineers and researchers in the field of materials related to transportation equipment, graduate students in various technical fields, and engineers and researchers belonging to material users to grasp the full picture of material development and multi-materials technologies. For the understanding of engineers and researchers who will work on multi-materials, this book explains the current state of technology and science in each field and explains the innovative results obtained by research in each field. On the Publication of this Book Contents Contributors 1 Background of This Book 1.1 Background 1.1.1 Initiatives for Global Environmental Problems and Decarbonization 1.1.2 Innovation and Materials Revolution 1.1.3 Significance of Research and Development of Structural Materials 1.2 Effects of Auto Body Weight Reduction on Suppression of CO2 Emissions and Improvement of Fuel Consumption 1.2.1 Relationship of Body Weight and CO2 Emissions and Fuel Consumption 1.2.2 Trends in Electrification of Automobiles 1.3 Initiatives Related to Multi-Material Design of Auto Bodies 1.3.1 Trends in Multi-Material Auto Bodies 1.3.2 Trends in Development of Automotive Materials 1.3.3 Trends in Automotive Welding and Joining Technologies 1.4 National Project for Structural Materials for Drastic Weight Reduction of Transportation Equipment 1.4.1 Innovative Structural Materials Association (ISMA) and the New Innovative Structural Materials Research and Development Project 1.4.2 Relation of R&D Items in Innovative Structural Materials Research and Development Project 1.5 Conclusion References 2 Materials Development 2.1 Steel Materials—World’s Highest Performance Automotive Ultra-High Strength Steel Sheets Using Medium- and High-Carbon Steels 2.1.1 Introduction 2.1.2 Representative Metallographic Structure of High Tensile Strength Steel 2.1.3 Functions of Carbon and Alloying Elements in High Strength Steel 2.1.4 High Strength Steel Sheets for Automotive Applications 2.1.5 Research and Development of Innovative Steel Sheets in the ISMA Project 2.1.6 Conclusion 2.2 Aluminum Alloys—Development of High Strength Aluminum Alloys for Automobiles and Aircraft 2.2.1 Directions of Alloy Development in the Project 2.2.2 Classification and Applications of Aluminum Alloys 2.2.3 Development of Automotive Materials 2.2.4 Development of Aircraft Materials 2.2.5 Conclusion 2.3 Magnesium Alloys—Development of Innovative Magnesium Alloys for Railway Car and Automotive Structural Materials and Establishment of Application Technologies 2.3.1 Introduction 2.3.2 Properties of Mg Alloys 2.3.3 Development of Flame-Retardant Mg Alloy High-Speed Railway Car Body [40] 2.3.4 Development of Innovative Mg Alloys for Automotive Applications and Application Technologies 2.3.5 Conclusion 2.4 Titanium Alloys—Development of Technologies for Energy Saving in the Titanium Production Process and High Performance in Titanium Materials 2.4.1 Introduction 2.4.2 Development Results 2.4.3 Conclusion 2.5 Carbon Fiber—Development of a New Precursor Polymer Not Requiring a Flame-resistant Treatment and Microwave Carbonization Technology 2.5.1 Introduction 2.5.2 Significance of the Development of the New Carbon Fiber Precursor 2.5.3 Development of Solvent-soluble Flame-resistant Polymer [73] 2.5.4 Carbonization Technology with Microwaves 2.5.5 Conclusion 2.6 Carbon Fiber Reinforced Plastic—Mass Production Technology for Thermoplastic CFRP Structure 2.6.1 Introduction 2.6.2 Objectives 2.6.3 Current Status of Materials (Technologies) in the Field 2.6.4 Summary of Research and Development Results 2.6.5 Trial Production of Vehicle Part Components with Developed Materials 2.6.6 Conclusions References 3 Materials Integration—Data-Driven Approach to Materials Design Using Simulation and Database 3.1 Introduction 3.1.1 What is Materials Integration (MI) System? 3.1.2 Examples of MI Development to Date 3.2 Purpose of MI Development in This Project 3.3 Project Development Results (Development of MI Practical Use Technology for Performance and Life of Magnesium Material) 3.3.1 Development of Fatigue Life Prediction Module for Flame-Retardant Magnesium Alloy Welded Joint 3.3.2 Establishing Database Based on Fatigue Life Calculation for Welded Joint of Flame-Retardant Magnesium Alloy 3.3.3 Magnesium Alloy Fatigue Strength Prediction Based on Literature Data 3.3.4 Establishing Database for Flame-Retardant Magnesium Alloy Performance and Life 3.3.5 Establishing Model Formula for Flame-Retardant Magnesium Alloy Performance and Life (Fatigue Property, Mechanical Property, and Corrosiveness) 3.4 Conclusion—Platform Establishment and Future Prospects References 4 Welding and Joining 4.1 Multi-material Joining Technologies—Overview of Joining Technologies 4.1.1 Introduction 4.1.2 Car Body Weight Reduction and Multi-material Structure 4.1.3 Overview of Development of Joining Technology 4.1.4 Conclusion 4.2 Joining Technologies for Medium–High Carbon Steels—Challenge of Joining Technologies for Medium–High Carbon Steels that Change the Conventional Concept of Welding 4.2.1 Introduction 4.2.2 Welding Process 4.2.3 Friction Joining Process 4.2.4 Conclusion 4.3 Joining Technologies of Dissimilar Materials – Toward Establishment of Production Process for Multi-material Structure 4.3.1 Introduction 4.3.2 Joining Technologies of Dissimilar Materials for Aluminum/Steel 4.3.3 Joining Technologies of Dissimilar Materials of Metal/CFRTP 4.3.4 Anticorrosion Technology 4.3.5 Thermal Strain of Dissimilar Material Joints and Evaluation Analysis 4.3.6 Conclusion 4.4 Adhesive Technologies—Development of Innovative Adhesives and Establishment of Strength Design Methods and Durability Prediction Methods by Elucidating Interfacial Adhesion Mechanisms 4.4.1 Introduction 4.4.2 Basics of Adhesion and Technology Development in the Research 4.4.3 Representative Research and Development Results 4.4.4 Social Implementation and Future Prospects of Bonding 4.4.5 Conclusion 4.5 Joint Performance Database—Creating Database of Joint Technical Integration System Using Machine Learning Technology and Corrosion Fatigue Properties of Dissimilar Material Joints Considering Practical Use Environment 4.5.1 Introduction 4.5.2 Science and Technology of the Field 4.5.3 Representative Research and Development Results 4.5.4 Social Implementation and Future Prospects 4.5.5 Conclusion References 5 Analysis and Evaluation 5.1 Corrosion—Issues in Automotive Anti-Corrosion Design and Evaluation Methods 5.1.1 Introduction 5.1.2 Conventional Knowledge of Corrosion Protection Life of Automobile Corrosion 5.1.3 Corrosion of Substrate Steel ( 4 ) 5.1.4 “Development of Corrosion Behavior Analysis Technique for Ultra-High Strength Steel Sheets” in the Project (Overview) 5.1.5 Conclusion 5.2 Galvanic Corrosion—Issues in Corrosion Protection Design for Galvanic Corrosion of Dissimilar Materials and Evaluation and Analysis Methods 5.2.1 Introduction 5.2.2 Conventional Knowledge of Galvanic Corrosion 5.2.3 Research and Development on Galvanic Corrosion in Multi-material Structure Auto Bodies 5.2.4 Conclusion 5.3 Hydrogen Embrittlement—Search for the Mechanism of Embrittlement for Social Implementation of Ultra-High Strength Steel Sheets 5.3.1 Introduction 5.3.2 Conventional Knowledge of Hydrogen Embrittlement 5.3.3 Overview of Efforts in the Project 5.3.4 Conclusion 5.4 Field Overview of Nondestructive Testing—Quantitative Detection Ff “Flaws” Which Are Harmful to Structures 5.4.1 Introduction 5.4.2 Background and Targets 5.4.3 Nondestructive Testing Technologies to be Developed in this Project 5.4.4 Outline of Nondestructive Testing Technologies to be Developed in this Project 5.4.5 Social Implementation and Future Prospects 5.4.6 Application Examples of Nondestructive Testing Conducted in this Project 5.4.7 Conclusion References 6 Structural Design 6.1 What is CAE?—Outline of Computer-Aided Analysis/Design Technologies 6.1.1 Introduction 6.1.2 Current State and Future of CAE Technologies 6.1.3 Conclusion 6.2 Topology Optimization—Development of New Design Method to Create High-Performance Automobile Body Structure 6.2.1 Introduction 6.2.2 Concept of Topology Optimization 6.2.3 Conclusion 6.3 Multi-material Design—Significant Weight Reduction Through Optimization of Material Arrangement and Shape 6.3.1 Introduction 6.3.2 Multi-material Automotive Body Design 6.3.3 Conclusion 6.4 Application of Topology Optimization to 3D Additive Manufacturing—Further Weight Reduction by Application of 3D Additive Manufacturing 6.4.1 Introduction 6.4.2 Overview of Metal Additive Manufacturing Technologies 6.4.3 Efforts for Multi-Materialization 6.4.4 Efforts in This Project 6.4.5 Conclusion References 7 Prototyping of Multi-material Parts—Efforts to Realize Practical Application of Innovative Materials and Technologies 7.1 Introduction 7.1.1 Meaning of the Prototyping 7.1.2 Part Prototyping in Overseas Projects 7.2 Organization 7.3 Evaluation Items 7.3.1 Study of Application of the Innovative Steel Sheet to the A-pillar 7.3.2 Study of Application of the TWB Manufactured by FSW to the B-pillar 7.3.3 Matters of Study with a Simulated Pillar to Which Dissimilar Material Joining Between a Steel Sheet and CFRP is Applied 7.3.4 Study of Application of the Innovative Aluminum to the Front Side Member and the Side Sill 7.3.5 Study of Application of the Innovative Magnesium to the Hood 7.3.6 Dissimilar Material Joining Between CFRTP and Aluminum in the Multi-material Door 7.3.7 Study of Application of the CFRP/CFRTP Composite Panel to the Roof 7.3.8 Matters Concerning Study of a Floor Made of LFT-D 7.4 Outline of the Result of Evaluating the Innovative Materials and Technologies 7.4.1 Study of Application of the Innovative Steel Sheet to the A-pillar 7.4.2 Study of Application of the TWB Manufactured by FSW to the B-pillar 7.4.3 Study of Application of Dissimilar Material Joining Between a Steel Sheet and CFRP to a Simulated Pillar 7.4.4 Study of Application of the Innovative Aluminum to the Front Side Member and the Side Sill 7.4.5 Study of Application of the Innovative Magnesium to the Hood 7.4.6 Application of Dissimilar Material Joining Between CFRTP and Aluminum with the Multi-material Door 7.4.7 Application of the CFRP/CFRTP Composite Panel to the Roof 7.4.8 Floor Made of LFT-D 7.5 Social Implementation and Future Prospects 7.6 Conclusion 8 Recycling and Lifecycle Assessment 8.1 Recycle—Technical Development for Material Circulation 8.1.1 Introduction 8.1.2 Recycling Technique for Aluminum and CFRTP 8.1.3 Representative Research and Development Results 8.1.4 Implementation in Society and Vision of the Future 8.1.5 Conclusion 8.2 LCA—New Lifecycle Assessment (LCA) Method for Evaluating the Effects of Alternatives to New Materials on the Environment, Economy, and Society 8.2.1 Introduction 8.2.2 Inventory Data Required for LCA 8.2.3 Lifecycle Inventory Analysis for Materials 8.2.4 Representative Research and Development Results 8.2.5 Implementation in Society and Vision of the Future 8.2.6 Conclusion References 9 Review and Future Development 9.1 Evaluation of the Project from the Viewpoint of TRL 9.1.1 Overview of TRL 9.1.2 TRL Evaluation of the Project by Field of Technology 9.1.3 Recommendations for the Future 9.2 Future Development by Formation of Centers by Research Field 9.2.1 Introduction 9.2.2 Features of Technical Field Centers 9.2.3 Requirements for Technical Field Centers [4] 9.2.4 Construction of Technical Field Centers by Public Organization Project Participants [5, 6] 9.2.5 Future Outlook References