Page 357 - Handbook of Materials Failure Analysis

CHAPTER

Fatigue failure analysis of

welded structures: An 14

overview and A case study

Seyed B. Behravesh, Elfaitori Ibrahim, Hamid Jahed
Fatigue and Stress Analysis Laboratory, Mechanical and Mechatronics Engineering
Department, University of Waterloo, Waterloo, ON, Canada

CHAPTER OUTLINE

1 Introduction ..................................................................................................... 355
2 Fatigue Modeling of Welded Structures by Local Approaches .............................. 360
2.1 Fracture-Mechanics Approach ...........................................................360
2.2 Structural Stress Approach ...............................................................362
2.3 Local Notch Stress/Strain Approach ...................................................365
3 Case Study: Fatigue Life Assessment of an Automotive Demo-Structure ................ 366
3.1 Problem Statement ..........................................................................366
3.2 Self-Pierce Riveting .........................................................................367
3.3 Material Properties and Modeling ......................................................368
3.3.1 Material Properties ................................................................ 368
3.3.2 Material Modeling .................................................................. 368
3.4 Fatigue Modeling .............................................................................370
3.5 LSPR Specimen ...............................................................................372
3.5.1 Specimen and Testing ............................................................ 372
3.5.2 FE Modeling ......................................................................... 376
3.5.3 Simulation Results and Discussion ........................................... 376
3.6 Demo-Structure ...............................................................................378
4 Conclusion ....................................................................................................... 383
Acknowledgments .................................................................................................. 383
References ............................................................................................................ 383

1 INTRODUCTION

Fatigue is a mode of failure and is responsible for most of failures in mechanical
components and structures [1]. Fatigue is the process of progressive and localized
structural change in a material under a fluctuating loading [2]. In this definition,
the term “progressive” means the fatigue process occurs over a period of time,
although the fatigue failure happens abruptly. The term “localized” states that the
fatigue process operates at local regions rather than throughout the whole component

Handbook of Materials Failure Analysis With Case Studies from the Chemicals, Concrete, and Power Industries. 355
http://dx.doi.org/10.1016/B978-0-08-100116-5.00014-4
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