Research On Microstructure And Properties Of Spiral Bevel Gear Casting-forging Compound Process Formed

Automobile driving axle spiral bevel gears as the transmission power key part of automobile rear axle main speed reduction box that will be in demand and high quality requirements.before forming process of spiral bevel gear is only pay attention to the macro-process,and ignored the study of micro-structure.In fact the forming process is the combination of macro to micro.Macro research focus on material in the mold cavity filling effect,utilization and the service life of die,process selection,etc.Microscopic study focuses on the dynamic recrystallization, grain growth and tissue distribution.The study of micro-structure can guide macro process selection and parameters optimization of forming process.In this paper,through the computer simulated the spiral bevel gear casting compound forging process,and by means of the combination of macro and micro analyzed the organization and performance,which can provide the theoretical support for the optimization of process parameters.Casting compound forming process take fully advantage of the casting blocking advantage and the modification effect of forging,not only save material and energy but also improves the mechanical properties and performance of the product. In this paper,the author selects the technology mature and widely used sand mold casting to forming the gear blank for the spiral bevel driven gear belongs to small complex casting.And using Anycasting casting simulation software for simulating the casting filling and solidification process.besides,forecasting and analyzing the shrinkage porosity defect,research and determine the best pouring temperature.How to convert as-cast microstructure to as-forged microstructure and refined grain in order to improve the quality of the products. In this paper,the author use the simulation software DEFORM-3D simulated the process of forging the casting blank.Analyzed the temperature range of forging, the change of stress and strain, the metal flow law and dynamic recrystallization. In addition to, using the method of cellular automata(CA) simulated the change of grain in the forging, studied and analyzed the temperature, strain and strain rate how to effect the recrystallization.