Definition

Noun: A fatigue crack is a type of fracture or fissure that develops in a material, most commonly metal, as a result of fatigue. Fatigue is the progressive and localized structural damage that occurs when a material is subjected to repeated cycles of stress or strain, even if the maximum stress is below the material's ultimate tensile strength. A fatigue crack initiates at a point of stress concentration and propagates through the material with each stress cycle.

Usage

This term is primarily used in engineering, materials science, and industrial maintenance contexts to describe a specific failure mode in components and structures.

Examples

• The inspection revealed a fatigue crack near the bolt hole of the aircraft's wing spar.
• Engineers analyzed the fatigue crack to determine the number of load cycles the component had endured.
• Regular non-destructive testing is essential for detecting fatigue cracks before they lead to catastrophic failure.

Advanced Usage

• "Initiation and propagation of a fatigue crack": This phrase describes the two main stages of fatigue failure. Initiation is when the crack first forms, often at a microscopic flaw. Propagation is the stage where the crack grows with each stress cycle.
• "Fatigue crack growth rate": A key engineering parameter that measures how quickly a crack lengthens per stress cycle, which is crucial for predicting a component's remaining service life.

Variants and Related Words

• Fatigue (Noun): The phenomenon of progressive damage caused by cyclic loading. (e.g., )
• Fatigue life (Noun): The number of stress cycles a material can withstand before failure occurs.
• Stress concentration (Noun): A location in an object where stress is significantly higher, often serving as the initiation site for a fatigue crack.

Synonyms

• Fatigue fracture
• Fatigue failure (This is a broader term for the overall failure event, of which a fatigue crack is a part.)

Related Phrases

• "To arrest a fatigue crack": To stop or halt the growth of a fatigue crack, often through design features or repair techniques.
• "Fatigue crack inspection": The process of examining a structure or component specifically to find fatigue cracks.

Noun

1. a crack in metal resulting from metal fatigue