Annealing
Definition
The heat-induced reorganisation of the crystal structure of steel at temperatures above approximately 720°C, resulting in reduced hardness and tensile strength; measurable post-fire and used to estimate whether a steel member reached annealing temperature during the fire.
Related terms
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- ASTM E1618
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- Char-Depth Probe
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- Inverted-Cone Pattern
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- U-Pattern
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- V-Pattern
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Explained in
- Origin and Cause: V-Patterns, Char Depth, Electrical IndicatorsThe heat-induced reorganisation of the crystal structure of steel at temperatures above approximately 720°C, resulting in reduced hardness and tensile strength...