Secondary Recrystallization
Secondary recrystallization is the uncontrolled growth of large grains in a fine-grained matrix, resulting in loss of properties.
Physicochemical Mechanism of Action
Secondary recrystallization occurs when a metal sample is subjected to elevated temperature and mechanical stress. The grains grow unevenly, leading to coarsening of the microstructure.
Metallurgical Relevance & Welding Risks
These processes can lead to a loss of strength and toughness. Material performance can be severely affected, especially when grains become very large. This can result in cracking and failure in service.
Workshop Practice & Instructions
To avoid secondary recrystallization, high cooling rates should be maintained during welding. This means the weld should be cooled quickly to achieve a finer grain structure. For steels with high carbon content, it is especially important to control the cooling rate.