Research On Warm Extrusion Of Gear Shaft Base On FEM Technology

Spur gears are important mechanical-driven parts, which are widely used in the automobile and mechanical industry. Low availability of material and productivity and high cost of production, cutting which is the conventional processing of gears production is hard to meet the demand of manufacturing. Compared with the conventional method, the plastic forming technology has many advantages, such as great reduction of raw material and subsequent machining, considerable improve the competitive power of industrial organization, and marked increase the mechanical property because the fibres of metal are not been cut off. Nowadays, producing gear through this technology are more and more being paid attentions to.Take the warm extrusion of spur gear as the research object, the numerical simulation of forming process and die wear are studied, which is in favor of improving the level of process designing, increasing the quality of the part and the service life of die.There are some major influencing factors in the warm extrusion of spur gear, such as the temperature of extrusion and die preheating, the half cone angle of female die, the speed of extrusion, lubricating and friction condition and so on. The influence conditions of the processing parameters mentioned above are investigated by DEF0RM-3D with three-dimensional rigid-viscoplastic finite element model. Then the conclusions are drawn as follows: with the temperature of extrusion and die preheating increasing, the warm extrusion force is falling down;with the half cone angle of female die and friction factor reducing, the force is arising;and with the parameter of spur gear such as height, modulus and the number of teeth increasing, the force is also arising;while the speed of extrusion have not obvious effect on the force.Some regularities are found by simulation, such as the shrink flaw can be avoided by the rounding at the intersection of different diameter of the spur gear shaft;the appropriate shape of the transition curve from involute to root circle is in favor of improving the filling condition of die cavity and decreasing the forming force.Basing on Archard wear model, the rule of die wear is studied by simulation, and the relation between wearing depth and the times of die service is found by means of unitary linearly regression, then the service life of die is previewed.