Wuhan University of Technology Graduation Design (Thesis)

Stress-strain Distribution and Deformation Law of Fiber Metal Laminate Components in Thermo-pneumatic Forming of a Special Transportation Equipment

School: School of International Education

Specialty amp; Class: Automotive Engineering gj1502

Name: Chen Wanli

Tutor: Chen Yizhe

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Abstract

Fiber metal laminates (FMLs) have been paid more and more attention in the fields of electronics, automobile, aerospace and so on, for its high strength, high modulus, excellent shock absorption and fatigue resistance. Compared with other traditional composite materials, FMLs, as a new composite material, combine the advantages of metal materials and fiber composites, and have become a research hotspot in recent years. However, the failure mechanism of new fiber metal laminates are still in its infancy. The strength prediction of composite materials depends on the accurate stress-strain response of materials under external force. Due to the poor strength and toughness of composite laminates and the weak interfacial layer, the properties of composite laminates are limited. Carbon fiber aluminum alloy laminates not only meet the requirements of material lightweight, but also meet the requirements of structural lightweight. Therefore, it is of great theoretical significance and practical value to study the preparation process, basic mechanical properties and low-speed impact properties of new hybrid fiber alloy laminates.

In this paper, the stress - strain distribution and deformation rule of carbon fiber - aluminum alloy composite were studied. On this basis, the basic mechanical properties of laminated plates were evaluated. Due to the existence of two main components of metal laminates, namely metal plate and reinforced fiberboard, the mechanical factors of each component will affect the quality of the formed laminates. This paper was based on ABAQUS software. The model of composite laminates was simulated under three conditions: different carbon fiber properties, different fiber sequences and different thickness of laminates. The stress-strain curve was obtained and its basic mechanical properties were analyzed.

Key words: Carbon fiber aluminum alloy laminate, Thermoforming, ABAQUS performance simulation

Catalog

Chapter 1 Introduction 1

1.1Background and Significance of Selected Topic 1

1.2 Overview of Fiber Metal Laminates 2

1.2.1 The Characteristics of FMLs and the Research Status at Home and Abroad 2

1.2.2 Application and Development Trend of Fiber Metal Laminates 5

1.3 Forming Technology of Fiber Metal Laminate 8

1.3.1 Main Forming Technology and Development of Fiber Metal Laminate 8

1.3.2 Application Status of Hot Forming Technology 11

1.4 Research Content and Significance 13

1.4.1 Study on Hot Forming of Metal Fiber Laminates 13

1.4.2 Research Purpose and Significance 14

Chapter 2 Specimens and Research Methods 16

2.1 Carbon Fiber/Aluminum Alloy Laminate Material 16

2.1.1 Carbon Fiber 16

2.1.2 Aluminium Alloy 19

2.2 Shape and Size of Specimen 20

2.3 Finite Element Analysis Model 21

2.3.1 Structure Design of Carbon Fiber Aluminum Alloy Laminate 22

2.3.2 Design of Carbon Fiber Aluminum Alloy Laminate 24

2.3.3 Finite Element Modeling of Carbon Fiber Aluminum Alloy Laminates Based on ABAQUS 26

Chapter 3 Analysis of Deformation Process of Fiber Metal Laminates under Hot Air Pressure 29

3.1Deformation Process of Laminates 29

3.2 Stress Distribution and Variation of Laminates 33

3.2.1 Stress Distribution of Aluminum Alloy Layer 34

3.2.2 Stress Distribution in Fiber Layer 36

3.3 Distribution and Variation of Laminate Wall Thickness 38

3.3.1 Wall Thickness Distribution of Aluminum Alloy Layer 38

3.3.2 Wall Thickness Distribution of Fiber Layer 41

3.3.3 Stress-strain Curve of Fiber Metal Laminate 41

Chapter 4 Analysis of Influencing Factors on Thermobaric Forming of Fiber Metal Laminates 46

4.1 Effect of Mechanical Properties 46

4.1.1 Effect of Mechanical Properties on Stress Distribution 46

4.1.2 Effect of Mechanical Properties on Wall Thickness Distribution 49