Development of ultrasonic techniques for process control in iron and steel making

The paper highlights the potential of ultrasonic C scan image analysis system using 5 and 10 MHz focused beam transducers to optimize electromagnetic stirring parameters during continuous casting of steel billets and overall assessment of billet quality including its cleanliness level. The ultrasonic C scan image plot could also reveal columnar and equiaxed grain structure in these billets and the effect of electromagnetic stirring on the change in equiaxed zone could be estimated. This technique also helped in reducing split end and cracking problem during hot rolling of continuously cast billets for thermo mechanically treated steel bars. An attempt was also made to measure viscosity and melting characteristics of mould powder slags used in continuous casting of steel using normal shear wave transducers. The experimental results show the possibility of using such technique for on-line measurement of viscosity and break temperatures of iron making as well as steel making slags/fluxes.