Incubation Period of Recrystallization
The incubation time is the time during which no visible new grains form after cold working, even though the deformation energy is active. It depends on the ambient temperature and the prior strain.
Physical-Chemical Mechanism of Action
After cold working, a portion of the deformation energy remains stored in the material. This energy is slowly released as the material adjusts and forms new, stress-free grains. The incubation time refers to the period during which this nucleation is not yet visible.
Metallurgical Relevance & Risks in Welding
An overly short incubation time can lead to insufficient grain formation, which impairs the toughness and formability of the material. An overly long incubation time can lead to recrystallization occurring too slowly, which again can impair the mechanical properties.
Workshop Practice & Action Guidelines
To ensure an optimal incubation time, the material should be formed at a constant temperature after cold working. The exact time depends on the specific properties of the material and the desired mechanical properties. A general goal is to choose an incubation time between 10 and 30 minutes to ensure sufficient grain formation.