Study On V-shaped Steel Rail Quenching Temperature And Stress Field

V-shaped rail is a key part on a universal grinding tool. In the entire manufacturing process,there are many heat treatment processes in order to ensure the performance requirements of steel rails.During the quenching,uneven thermal stress and phase transformation stress often appears because of the non-uniform internal temperature distribution and microstructure transformation.The existence of these stresses will directly affect the properties and service life of parts.Therefore,the study of the formation of quenching residual stress and impact factors is extremely important.However,experimental methods can only measure the surface residual stress of quenched specimen.With the development of numerical analysis techniques,the method using finite element technique which can reveal the formation,size and distribution of quenching residual stresses has become effective.Based on the basic principles of heat transfer and thermal elastic-plastic theory,this paper made the computer simulation for the quenching process of GCr15â…¤-shaped rail with the finite element analysis software called ANSYS.Firstly,the three-dimensional model of transient temperature and stress field is established with the finite element method and the non-linear change of thermal parameters, heat conduction and other boundary conditions are all considered. With the model,dynamic analysis,precise calculation and prediction in various time period of the temperature field in quenching process can be realized.Secondly, based on incremental theory and the corrensponding elastic-plastic constitutive equation,assuming that the material satisfying the Prandtl-reuss plastic flow rule in the palstic zone.this paper made simulation of stress field and the eventual residual stress in the queching process considering the material nonlinearity,phase transformation plasticity and other factors.This is helpful to estabish the theoretical analysis model for the further study of the parameters impact on heat treatment process.Finally,this paper has studied the impact on the quenching temperature and stress field under different conditions using the theoretical analysis model,such as heating temperature and cooling medium.It can be helpful to find the stress concentration and crack sites which are easy to appear and lay the foundation for intelligent control of the quenching process.