Simulation study of the punching forming process and die wear of spur gears.

As an important transmission component, the spur gear has been widely used in automobiles and various mechanical equipment. However, spur gears are usually produced by the hobbing and shaving, which inevitably reduces the service strength and service life of the gear. In this paper, the one-step punching forming process of spur gear is presented. Compared with the traditional gear machining process, the process not only avoids the destruction of the metal flow line but significantly decreases the material cost. The effect of tooth filling and equivalent strain accumulation on gear forming quality was investigated by finite element simulation. The effects of upper die punching speed, lower die preheating temperature, and friction coefficient on lower die wear during forming were studied by response surface method. The optimum process parameters of punching of spur gear were a lower die preheating temperature of 280 ℃, friction coefficient of 0.27, and upper die feed speed of 8.3 mm/s, respectively. It is predicted that about 110,000 gears can be produced before the wear failure of the lower die. On the basis of the finite element simulation results, the gear punching experiment is performed. The experimental results are in good agreement with the simulation results, and the metal flow line at the tooth is uniform and continuous, which verifies the reliability of the one-step punching process. [ABSTRACT FROM AUTHOR]