Physical Simulation And Multi-Field Numberical Simulation On Universal Rolliing Process Of Heavy Rail

Rail transport plays so important a role in the country's economic development. Better steel rail with higher reliability is in requirement while the rail transport gets faster, heavier and busier day by day. In the nowadays, universal rolling is the main method of steel rail's production. In order to go further in improving the quality of the steel rail, first of all, new types of steel material for rail with better property both in physics and chemistry should be created. Secondly, the structure of the rail could be reformed by approaches of optimization. Last but the most important, the application of rolling-control and cooling-control technologies in the universal rolling processes help people to elevate the quality of the rail production through improving the microstructure, because that can be achieved at the current level of facilities, is not only the most easy to implement, but also the lowest cost way.In this article, most of the works focus on the microstructure evolution behaviors of a common-used material in heavy rail production named U75V in the condition of hot deformation in the hope of predicting and controlling properties. Both the methods of physical simulation and numerical simulation were adopted, and a multi-field computer emulation was carried out.Firstly, some physical simulation tests were done on the Gleeble3500 thermo-mechanical simulation system with samples of U75V material. From the tests ture stress-strain curves, the mathematical models of dynamic and static recrystallization, and also the relative mathematical model of grain size were gained as the constitutive equation which is going to be used in the physical simulation.Which followed is the modeling of a geometrical universal rolling process according to real sizes of UIC60 rolling mill using three-dimensional modeling software PRO-E, that was transformed into a processing model of FEM analysis by designing the universal rolling schedules.Finally, a commercial finite element software DEFORM-3D was introduced as a platform to do a multi-field numerical simulation which include thermol, mechanics and the evolution of microstructure using the mathematical models above and reasonable boundary condition. the pass and the pass interval of the stress field, strain field, strain rate, temperature field, the metal flow field and other macro-physical parameters, as well as the percentage of recrystallization, grain size and other microscopic physical parameters. Owing to reasonable and correct simulation results, it can be a reference for the improvement of the production process.