Rolling Deformation And Microstructure Evolution Of Heavy Cylinder Considering The Shear Effect

The heavy cylinder is mainly used in the environment of high temperature,corrosion and high pressure due to huge size.Therefore,it has very high quality and performance requirements.At present,the application of rolling forming has become the one of the main development trend.The rolling process is a complex physical process with multi field and multi factor coupling.The final microstructure determines the comprehensive performance of the product to a large extent,which directly affects the forming quality of the heavy cylinder.In this paper,the deformation behavior and microstructure evolution in the process of heavy cylinder are systematically analyzed and studied by the method of experiment and finite element simulation.The main research work is in following filed:(1)The common cylinder and SCS compression shear specimens of different sizes were designed considering the rolling shear zone in the rolling deformation zone of heavy cylinder.Through the high temperature compression experiment,the plastic deformation characteristics of two kinds of specimens under different deformation conditions were studied,the influence of shear effect was analyzed,and the corresponding deformation resistance model was established.The finite element model of rolling process was established,and the influence of shear effect on rolling force was analyzed;(2)The microstructure of the two specimens was studied.The influence of macro thermal parameters on the dynamic recrystallization of the specimens under the same deformation condition was studied,and the dynamic recrystallization dynamic models of the two specimens were established.Based on the experimental results,the partial grain sizes were reasonably predicted,and the mathematical models of the dynamic recrystallization grain sizes of the two specimens were established;(3)Based on ABAQUS finite element software and python language platform,a subroutine was developed to study the evolution of microstructure.The subroutine was coupled with the finite element model to form the thermal-force-microstructure models.The reliability of the model was verified by the high temperature compression experiment and the finite element model of the rolling process;(4)Based on the verified coupling model,the microstructure evolution characteristics in the rolling process were analyzed systematically.According to whether the shear effect is considered or not,the dynamic recrystallization distribution and the average grain size were studied from the axial,circumferential and radial paths of the rolling process.