Creep

What is Creep?

Slow, time-dependent plastic deformation of a material under sustained stress, accelerated by temperature. It becomes significant above roughly 0.4 of a material's absolute melting temperature — exactly the regime turbine blades operate in.

The five clues

Engineerdle #45 described Creep with five clues, revealed one at a time from hardest to most direct. Each clue points at a different property of the concept.

1. 01It happens under a constant load, given enough time.
2. 02It matters above roughly 0.4 of the melting temperature.
3. 03Its curve has primary, secondary and tertiary stages.
4. 04It's the life-limiting mechanism for turbine blades.
5. 05Time-dependent plastic deformation below the yield stress.

More Materials concepts

• Young's ModulusPuzzle #55