Research On The Mechanical Impact Pre-hardening Technology Of High Manganese Steel Frog

The High manganese steel frog material research and industry development has been the most crucial part of the high speed railway.In order to effectively improve the service life of the high manganese steel frog,the researchers adopted many methods and ways,from the different point of view to ana lyze the material properties and the using state of the high manganese steel frog.As the most widely used part of the manganese steel,the railway frog inherited many advantages of the high manganese steel,and some obvious flaws as well.The main perform ance is that the low hardness of the high manganese steel material is difficult to load the railway transportation.However,the high manganese steel frog has excellent work hardening property,which makes the surface of the material have obvious hardening phenomena after shocking on its surface,and which guarantees the stability of the manganese steel frog.Although the theory of hardening mechanism of high manganese has never been unified by experts and scholars at home and abroad,its ability of work ha rdening is the focus of the research of scholars in engineering field.In railway transportation system,using the special properties of manganese steel to optimize the using-performance of the materials to improve the service time of railway frog and redu ce the operation cost of railway transportation system.The purpose of this article is using the experiment to simulate the high manganese steel material by the huge impact load of the actual situation.The first part of the research is the mechanical work hardening test of high manganese steel frog.High manganese steel frog in railway transportation system mostly influenced by their own conditions,the impact load is huge and not easy to concluded,so the selection of common engineering equipment as the r esearch object is more suitable.Calculating the impact energy parameters,which can used by design the self-made mechanical shock test bed,and the impact load hardening rule of high manganese steel in the actual engineering is simulated.The result shows that there is a critical impact work value of high manganese steel,and the surface of the material will show obvious hardening effect when the impact work size exceeds the value.However,the critical impact work of high manganese steel frog material is not unique,and its size changes with the change of material organization structure.Therefore,this article puts forward the high manganese steel mechanical shock hardening relativity of the size of the critical impact energy,its meaning is not only a me asure of work hardening rule and mechanism,and the efficiency of work hardening of high manganese steel material have great influence.The second part of the study is the constitutive equation of high strain rate of high manganese steel.Although there are relatively complete constitutive parameters of high manganese steel frog material,it is inevitable that there are some deviations,and the strain rate has great influence on the deformation of metal materials.In order to accurately simulate the hardening effect of high-manganese steel frog impact test,the constitutive equation of high manganese steel frog can be reconstructed by means of tensile experiment.The Johnson-Cook constitutive model of high manganese steel frog material has not only enriched the model database of this material,but also provided the theoretical basis for the simulation of ABAQUS finite element software.The last part of the research is to use the finite element software ABAQUS to simulate the mechanical impact hardening proces s of high manganese steel frog.It is very difficult to observe the process of internal stress and strain of materials only though the mechanical impact test,and the observation results are more intuitive and simple through finite element simulation.Simu lation data show that the impact test result in accordance with the basic data results,the surface hardness can reach 33.2 HRC,the depth of hardening layer is 12.1 mm,meet high manganese steel frog pre hardened service requirements.