Parameter Optimization Of Laser Quenching And Die Life Prediction For CrMo Cast Iron Covering Part Die

Wear resistance and life of automobile covering part die have a direct impact on the quality and manufacturing cost of automobile covering part.The manufacturing quality of automobile covering part will inevitably decrease when the die is worn.It is necessary to strengthen the surface of die in order to ensure the wear resistance of die.Of course,if the service life of die can be predicted,enterprises can repair and debug the die in time to improve the manufacturing quality and reduce the manufacturing cost.In this paper,the surface strengthening of CrMo cast iron,a common material for automobile covering part die,is carried out by the laser quenching process.The dynamic heat source load is applied to CrMo cast iron by ABAQUS software to realize the simulation of laser quenching.Through the analysis of temperature field,the characteristics of laser quenching are explored,and the depth of hardened layer is calculated and predicted.The laser quenching test of CrMo cast iron was carried out by TH-3DC3000 laser processing system.The microstructure changes of the material were observed by metallographic microscope and scanning electron microscope,and the hardness of the sample surface and hardened layer was measured by microhardness tester.The effects of different laser quenching parameters on CrMo cast iron were explored,and the optimal process parameters were determined by comparing with the simulation results.After the surface strengthening treatment of the automobile covering part die,the service life of die has been significantly improved,but there is still the problem of die wear.Friction and wear tests were carried out by MMW-1A multifunctional vertical friction and wear tester.The sample material is laser-quenched CrMo cast iron,and the wear coefficient K is calculated according to the test results.Optimize the traditional Archard wear model,the wear coefficient K is transformed into a dynamic wear coefficient that changes with contact pressure and sliding velocity.Combined with the change curve of the hardness of die hardened layer after laser quenching,the dynamic wear model is established according to the results of the wear test.The secondary development of ABAQUS software with Python language was used to calculate the wear depth of the automobile covering part die,and the service life of die was predicted according to the calculation results.In this ABAQUS/Python script,the calculation is based on the dynamic wear model.The wear coefficient is updated in real-time according to the actual working conditions of each node of the die during the calculation.Comparing the calculation results of the die wear depth of the traditional Archard wear model and the dynamic wear model,the die wear depth calculated based on the dynamic wear model is lower than that calculated by the constant wear coefficient when the stamping times are the same.To sum up,this paper studies the effects of different laser quenching process parameters on the microstructure and hardness of CrMo cast iron and establishes the best combination of process parameters.By optimizing the traditional Archard wear model,the dynamic wear model is established.After the secondary development of ABAQUS software with Python language,the die wear depth is calculated,and the service life of the die is predicted according to the calculation results.