Speaker
Description
Quality control for efficient steel processing is extremely important with the need to decarbonise production, produce steels to tighter material property constraints. Thermo-mechanical controlled processing and the models for predicting microstructural development need input from smart sensing technologies to improve their capability, particularly for advanced high strength steel grades that are demanding to produce. Real time control of steel production requires sensors that can withstand and measure at high temperatures during processes such as hot rolling and run out table cooling.
Direct measurement in-situ during processing of steel microstructure is challenging, with electromagnetic (EM) sensors now being regularly employed during strip production, primarily for inspection during cold strip processing. EM sensors have, more recently, been used for hot strip steel monitoring. Physical simulation of industrial run out table conditions combined with high temperature electromagnetic sensing, along with advanced modelling techniques, is needed to support and expand this development to wider applications. For example, electromagnetic sensor arrays are in development that can be used for assessment for varying strip widths, thicknesses and products with complex geometries such as rod and wire. This paper reports on a laboratory demonstration furnace-roller table with embedded EM sensors where variable flowrate water cooling regimes can be imposed to generate specific steel phase transformation behaviour. The EM sensors can be used for monitoring of phase transformation, and with feedback for control of cooling to achieve specific microstructures. Trials using different steel products and chemistries have been completed and related to modelling results. It has been shown that it is possible to measure phase changes at high temperatures during steel cooling from normalising temperatures for plate, strip, rod and wire applications. EM sensor feedback can be used by steel processors to integrate into mill control systems for accurate product metallurgy and mechanical property control.