The Numerical Simulation Of Carburizing Cylindrical Gears In Quenching Process

Heat treatment is the last procedure of the gear's hot-procession, whereas carburizing and quenching is the important step of the heat treatment. After carburizing and quenching, residual stress is formed on gear's tooth surface. The residual stress has an obvious influence on gear's fatigue strength, processing precision and the ability of resisting to be eroded. But in reality, there are many restrictions and deficiency in the traditional methods for measuring the residual stress distribution, it also hardly track the surface and inner stress accurately. Therefore, it is very useful to of study the stress field and final residual stress distribution of gear in carburizing and quenching procession by the finite element simulation.Based on the principle of heat transfer, and the principle of thermal elastic-plastic, it uses the finite element software ANSYS to research and simulate the carburizing and quenching cooling process of gear. According to the simulation needs, the continuous change parameters of carburizing layer is simplified to step change, and it uses the APDL language to simulate all the process, which includes the creation of model of cylindrical gear and carburized layer, the input of all material parameters, mesh of model, and the solution of the temperature field and stress field. It can modify the size of gear and the thickness of carburizing layer by adjusting the parameters of the command flow, which can realize the parametric analysis for quenching process of carburizing gear.Through the simulation and calculation, this paper researches the changing of the temperature and stress field in the whole quenching process of carburizing cylindrical gears, and it also gets the final distribution of residual stress on gear tooth surface. In addition, this paper analyzes the distribution feature of residual stress field, which provides a theoretical reference for determining the gear carburizing technology.Taking the above analysis of residual stress as the initial stress, it researches the residual stress field on the performance of the gear, it examines residual stress on the protection for the gear from the numerical point of view, and it studies the effect of different carburizing layers'thickness to the residual stress distribution, and proposes the reasonable model.