This article presents the results of an experimental study of cold rolling TRB strips of S235JR steel applying one grooved roll and another plain roll. The purpose of the study was to determine the possibility of rolling TRB strips with the technology studied, depending on the dimensions of the charge and the number of rolling passes. In addition, the possibility of reducing the magnitude of TRB strip curvature due to the introduction of asymmetry into the process was investigated. The effect of the rolling process and shape variation on the material’s hardening was evaluated by measuring hardness. Based on the results, it was determined that the greater the initial thickness of the charge, the higher the shape tolerances can be obtained. In addition, hardness variation was observed on the cross-section of TRB strips, which decreased with increasing values of plastic deformation. It has also been shown that it is possible to reduce the curvature of the TRB strip due to the use of double asymmetry.

DP600 steels are characterized by a dual phase ferritic-martensitic microstructure, to which they owe their exceptionally favourable combination of high strength and good ductility. One of the production methods for this grade of steel is the hot rolling process. Despite the fact that these steels have been produced on an industrial scale for almost 40 years, they are still being studied intensively, with new research on the formation of their microstructure and properties published every year. This article focuses on the characteristics of DP600 steel produced on a hot rolling mill for applications in automotive industry. The article presents the results of mechanical properties tests and microstructure analysis of DP600 steel obtained in an industrial hot rolling process. The general characteristic of DP600 steel presented in this article, is supplemented with statistical analysis of correlations between chemical composition, selected process parameters and mechanical properties of hot rolled DP600 steel.