Advanced Structural Analysis/Part I - Theory/Failure Modes/Fatigue/Crack Initiation

1. Introduction
2. Fundamentals
3. The Wöhler Curve
4. The Similarity Principle
5. Loading
6. Additional Influences

Introduction

The crack initiation phase normally spans the majority of the considered life-cycle in non-welded parts. In fact, it is common practice in many applications to approximate the total fatigue life by the duration of the crack initiation period.

The initiation process is bound to the material surface, and is regarded as ended when subsequent fatigue damage no longer depends on the surface conditions.