Study of the Possibility of Improving the Microstructure of Metal during Hot Rolling of Steel 20 Sheets

The main mechanical properties of metal, including ductility, strength, and impact toughness, largely depend on its microstructure. The possibility of significantly improving the microstructure of metal, achieved by hot rolling sheets of grade 20 steel, is demonstrated. An experimental study of the dependence of grain size on the ratio of work roll speeds has been performed in five modes. The experiments were conducted on a duo 400 industrial–laboratory mill of the A.P. Zhilyaev Mechanics of Gradient Nanomaterials laboratory of Federal State Budgetary Educational Institution of Higher Education of G.I. Nosov Moscow State Technical University. As a result, a process flowsheet for hot asymmetric rolling of the grade 20 steel sheets was developed, ensuring a uniform metal microstructure across the entire thickness within a range of 1–3 μm.