Cold-rolled DP980 steel is widely used in the automobile industry. Hot-rolled coil is the raw material of cold-rolled DP980 steel, the head and tail parts of which are usually obviously stronger than the body part. The objective of this study is to improve the longitudinal performance uniformity of hot-rolled coils. The material properties of this steel, such as the dynamic continuous cooling transformation, the influence of the cooling mode before coiling, the cooling rate during coil cooling on the microstructure, and mechanical properties of cold-rolled DP980 steel were investigated through thermal simulation experiments and hot rolling experiments. Meanwhile, the temperature field of hot-rolled coil was analyzed using ABAQUS software, which was used to survey the cause of the longitudinal performance fluctuations of hot-rolled coils, combined with an investigation of the aforementioned material properties. The results illustrate that the average cooling rate of the head and tail parts are higher than that of the body part during coil cooling, which causes the longitudinal performance fluctuation of hot-rolled coils. Based on the temperature field of hot-rolled coil, obtained by FEM, the parameters of the U-shaped cooling process were optimized and used in industrial applications.
This is an open access article distributed under the Creative Commons Attribution License
which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited