Infire – Strategy to increase the hot strip rolling performance in terms of surface quality, final properties and reproducibility

Situation:

Achieving high surface quality of hot rolled high strength steel strip and reproducible rolling results remains challenging:

• Primary scale residues and scale formed during rolling lead to surface impairments.
• Influences and interrelations of process conditions on product quality are poorly known.
• As steel grades with higher strength are demanded, hot rolling conditions change.

Solution:

• Adopting primary scale residues and finished strip monitoring systems for prognosis of scale defects
• Investigation on sensitivity of the rolling result on process parameter
• Novel methods to control scale growth and fracture behaviour with the optimisation of rolling parameters as well as rolling actuators and application of oxide modifiers
• Create a model to predict scale behaviour

Operational benefit:

• Minimisation of effects of scale on the final surface texture and strip mechanical properties
• Improvement of the surface quality of critical high alloyed steel grades by understanding and conditioning scale formation during rolling and cooling
• Definition of the optimum rolling and cooling conditions for industrial application towards a significant improvement of the quality of the final product for high value added steels
• Enabling existing plants to handle new kind of high strength steel grades in a more efficient and reproducible way

• material properties
• Scale conditioning
• secondary scale formation
• surface properties