Numerical Simulation On Quenching Deformation Control Of Bevel Gear

As one of the most important parts in the machinery industry,bevel gears are widely used in large equipment and precision instruments.The performance of the machines is affected directly by the processing qualities.However,severe deformations such as plane warpage,inner hole distortion and tooth shape change,often take place during quenching processes because of its high precision and complex structures.In this situation,it has great significance in controlling the deformation of bevel gears.With the rapid development of computer technology,there are many researchers using finite element simulation technology to study quenching deformation.Based on ABAQUS,a reasonable physical model is established,the quenching process of 9310 steel bevel gears is simulated,and the change of temperature field and stress field is studied in the cooling process.By optimizing quenching process parameters and simulating the pressure quenching,a reasonable scheme for controlling deformation is presented.Based on the basic theory of heat transfer and thermoplastic theory,the thermo-mechanical properties for quenching simulation process are determined.ABAQUS was used to simulate the quenching process of bevel gear,the change of cooling speed of the characteristic parts and the overall stress distribution of bevel gear quenching process was analyzed.According to the interaction characteristics between temperature field and stress field,the local stress concentration is caused by the larger thermal differential between inside and outside parts and the uneven cooling speed at each parts,and the uneven cooling speed leads to the asynchrony of the organization transformation.The larger deformation of the bevel gear is caused by these aspects.The bevel gear plane warping,inner hole distortion and the changing rule of the tooth profile changes could be effectively controlled by changing the quenching process parameters(quenching medium,quenching temperature,quenching medium temperature),the loading method of mould pressure and the magnitude of load.Simulation results show that choosing No.20 machine oil as the quenching medium,controlling the quenching temperature at840 °C,quenching medium temperature at 60 °C is the best process to control the quenching deformation of 9310 steel bevel gears.The overall deformation is effectively controlled by applying pressure on the inner circle and outer circle of the bevel gear at the same time,keeping the pressure on the inner ring of 15 MPa,the outer ring of 50 MPa.The plane warping was controlled at 0.12 mm,and the inner hole shrinkage decreased to 1.65 mm-2.0mm,and the inner hole distortion decreased to the lowest.