In this paper we present a mathematical model for evaluating the Lankford coefficient (LС) in automotive sheet steels as a function of the ferrite grain size after hot rolling, the degree of cold rolling reduction, the chemical composition, and the volume fractions of perlite and bainite in the final structure. Empirical parameters values of the model were determined using the experimental data base on average LC in 138 strips of 13 steel grades, produced at PJSC Severstal, with a significant range of chemical composition variation. Complementary, databases on calculated steel microstructure parameters after hot rolling, and after heat treatment of cold-rolled strips on a continuous annealing line were used when creating the model. There is a satisfactory agreement between the results of LC calculations made by the developed model and the experimental data. The mean absolute value of relative error in the calculations for considered steels is 7.1 %.Keywords: Mathematical modelling, Lankford coefficient, automotive steels, cold rolling, annealing
© 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.