Microstructure and Mechanical Properties of Strip Cast 1008 Steel after Simulated Coiling, Cold Rolling and Batch Annealing

Abstract

As-cast low carbon steel strips produced by twin roll strip casting process were treated by cold rolling and batch annealing. The microstructure and mechanical properties were compared to those of drawing and commercial quality strips. The mechanical properties of the as-cast strip are inferior to those of an industrial hot band due to the presence of Widmannstätten ferrite microstructure. After simulated coiling, cold rolling and batch annealing the ductility of the strip cast steel is lower than that of the industrial products, due to the hardening effect of small Cu-S precipitates and coarser iron carbides. However, for the strip cast steel processed according to a drawing quality (DQ) route, the mechanical properties are within the range of a commercial quality (CQ) product. Therefore, mechanical properties falling within the range of commercial quality steel can be obtained with strip cast steel without a hot rolling step if appropriate cold rolling and annealing treatment is used.