Study On Dynamic Recrystallization Behavior Of 06Cr19Ni9NbN Stainless Steel

In recent years, people’s requirements of stainless steel are increasing with the continuous development of industry and the improvement of social needs.Especially in the petrochemical industry,there’s a variety of corrosive media with a strong corrosive effect to the applied containers and pipes in production processes,while the 06Cr19Ni9 NbN single-phase austenitic stainless steel as the material of choice for chemical equipment components producing the nitric acid and sulfuric acid,not only because it’s good corrosion resistance,but also because the strengthening effect of nitrogen lead it’s ductility and toughness at a high level,thus resulting in a more widely used. The austenitic stainless steel can’t refine the crystalline structure through the phase change,nor can change its organization through the heat treatmentcan,so we can only change its final mechanical properties by the way of dynamic recrystallization.Thus,the establishment of a complete dynamic recrystallization model of 06Cr19Ni9 NbN steel is very urgent and important.The Gleeble-1500 D thermal simulated test machine is used for obtaining the stress-strain curves and microstructure of the material at different deformation through the thermo-simulation compression experiment to analysis how the temperature, strain rate and the reduction effects the dynamic recrystallization behavior in this paper.The study found that the dynamic recrystallization phenomenon is rather distinct with the rise of temperature and the increase of reduction.While,the high strain rate is not conducive to dynamic recrystallization.Then,combine with the stress-strain curves and microstructure of the material at different deformation determine the thermal deformation constitutive equation,the steady-state flow stress model,the peak strain and critical strain model, dynamic recrystallization fraction model and the dynamic recrystallization grain size model. Then,this paper analysis the dynamic recrystallization in different locations through plan strain compression under different deformation conditions,and study the basic characteristics of the plan strain compression through DEFORM simulation, then, combining with simulation results analysis how the temperature and reduction effect the percentage of dynamic recrystallization and average grain size.Finally,by comparing the experimental results with the simulation results of the grain size at the measuring points, and the small result errors verify the accuracy of dynamic recrystallization model.