Numerical Simulation On Thermal Performance And Quenching Process Of Hot Stamping Die Steel

Hot forming components such as high-strength steel stampings can effectively reduce the weight in order to lower fuel consumption, reduce emission, and ensure the safety performance of vehicles. High-strength steel stamping’s production has a high requirement on the hot work die material and its preparation process. Using casting method to produce hot-work die can greatly reduce the production cost. Cooling (heating) channels designed in interior of the hot die can significantly improve the cooling (heating) efficiency of components and cooling (heating) uniformity. Subsequently, heat treatment can improve the mechanical properties and fatigue properties of the mold, so the mold material for casting, heat treatment process can be put forward higher requirements. Currently, applied to such high life dedicated hot stamping die material and its preparation process is not mature, so the research on developing a new type of hot stamping dedicated hot stamping die steel and thermal processing is of great significance.Material performance simulation software JMatPro is widely used in CAE software to provide material performance parameters, assist researchers to design the alloy, the heat treatment optimization and predict material performance. This paper uses JMatPro to obtain a new design hot-work die steel(XSJ) of the equilibrium phase diagram, properties and TTT, CCT, and analyzes the influence of hot-work die steel alloy elements Cr, Mo, Si on its thermal conductivity so as to demonstrate the rationality of the new design chemical composition. Analysis show that the number of MC and M6C formed in XSJ hot-work die steel increases, and the M23C decreases, and the change of high temperature stability and good stability of MC type carbide to poor M23C6carbides is delayed, it is very useful for the material to get a more lasting high temperature strength and fatigue resistance, with the increasing content of alloying elements Cr, Mo, Si, the thermal conductivity has a downward trend, and the three elements of the influence on thermal conductivity is Si> Cr> Mo, so when designing the chemical composition, appropriately adjusting the content of chemical elements can improve the thermal conductivity. The thermal conductivity can maintain30～36w/(m℃) under the operating temperature of the hot work die steel, to improve the service life of steel.The numerical of the shaped curves channel hot work die is established, and quenching process of the hot work die is simulated in GRANTAS which is the heat treatment professional software. The temperature, organization, hardness stress and deformation field can be obtained in different time and areas. The influence of the heat treatment process parameters is researched on the model properties to put forward the reasonable heat treatment process. Eventually the heat treatment of quenching temperature at C℃, quenching medium3and quenching medium temperature at d℃can get high and evenly hardness, small deformation, so this process is selected as the heat treatment process of the hot-work die model.