Profile Strip Casting with Inline Hot Rolling: Numerical Simulations for the Process Chain Design

Abstract

A process to produce thin steel strips with an optimized cross-section has been recently developed at the Institute of Metal Forming (IBF) as possible alternative to tailor welding and cold profile rolling for the production of tailored flat products. This process was named profile strip casting and combines the advantages of twin-roll strip casting, such as energy efficiency and compact production route, with the attractiveness of tailored products for lightweight applications. A finite difference model for the thermal description of the complete process chain including solidification, air cooling, and rolling is presented in this work. The developed simulation tool is calibrated on the temperature measurements obtained with profile casting experiments and targets the investigation of thicknesses not achievable with the available equipment. The measured surface temperature difference between the thick and thin zone of the profile for a strip with a thickness of 1.5 mm in the thin and 2.2 mm in the thick section cast using selectively coated rolls was ΔT = Tthick - Tthin = 82 K after the casting gap and 109 K at the mill exit. The simulation indicates that increasing the thickness to 3.5 mm in the thin and to 5.1 mm in the thick profile zone the surface temperature difference results 26 K after the casting gap and 126 K at the mill exit.