Ferrite rolling

Abstract

The Uddeholm ferrite-rolling process is a high-deformation process and a thermomechanical treatment. The process has been designed for high-carbon and alloy types of steel strip. The reduction of about 80% is applied at a temperature of 600°−800°C, i.e. above the temperature at which ferrite recrystallizes and below that at which transformation to austenite occurs. The basic innovations concern mechanisms of spheroidization but ferrite rolling is now being used as an effective means of reducing processing costs and throughput times. A joint welding plant produces coils of the order of 10−15 t. A high-frequency heater and a medium frequency heater give short heating times with limited oxidation. Following the inductors are two 4-high stands in tandem, cooling equipment, a flying shear, and two coilers. Hard rolls were needed to resist wear and heat checking. The best solution was to produce a powder-coated compound roll in M3:2.