Niobium grain refinement mechanism
The niobium grain refinement mechanism prevents grain growth during rolling through dissolved niobium atoms and fine precipitates, which increases strength.
Physical-chemical mechanism of action
The niobium grain refinement mechanism prevents grain growth during rolling through dissolved niobium atoms and fine precipitates, which increases strength.
Metallurgical relevance & welding risks
Insufficient niobium grain refinement can lead to too large a grain, which reduces the toughness and formability of the steel. This increases the risk of cracks and reduces the service life of components.
Shop practice & action instructions
To optimize the niobium grain refinement mechanism, the rolling speed should be kept at least 10 m/s. The niobium content should be between 0.05% and 0.1%. At too low speeds or too low niobium content, grain growth cannot be prevented.