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Magnesium alloy as one of the lightest commercial structural metallic materials, it is the ideal material for lightweight, has a very important technical and economic value. The wheel hub as a rotating member of the vehicle on a high-speed movement, the weight can effectively reduce the energy consumption and to improve the acceleration and braking performance of the vehicle, to improve ride comfort and safety advantages. Using lightweight material replacement hub is an effective way to achieve this. But the structure of the existing wheels are developed for steel and aluminum alloy design. To magnesium alloy hub, material substitution service requirements of raw steel, aluminum alloy wheels, hub structure for structural redesign to ensure that the service performance and developing new molding process, and process characteristics of magnesium alloy to ensure the quality of product technology . In this study, finite element method Huatai wheel hub of aluminum, magnesium two kinds of material of the wheel hub to promote the magnesium alloy hub reasonable application Service Stress analysis to optimize the structure of the hub, reducing peak service stress, improve security hub. Also using numerical simulation software squeeze casting process of magnesium alloy wheels filling velocity field, temperature field and solidification of the solid-liquid phase distribution, solidification time and casting defects formed relationship studies to determine the best squeeze casting process parameters. According to the simulation results of the above analysis, to determine the best structure in the form of wheels and gating system, the extrusion casting mold design. The results are as follows: 1. Huatai wheels instead of the original two halves bolted structure, the overall design structure can simplify the manufacturing process, reducing the production of the fixture, saving manpower, material and financial resources, etc.. 2. Redesign the structure of the wheel hub for finite element analysis, analysis of centrifugal force, wheel rotation surrounding stress, the alternating displacement, modal impact, has an important role in the structural design of the wheels. 3 due to the lower modulus of elasticity of magnesium alloy, via the larger the elastic deformation of the overall bearing, for the same structural dimensions of the hub, but the material was changed from aluminum to magnesium alloy, the service stress peak decreased from 33.14MPa to 26.14MPa , a drop of 21.12%, easing stress concentration, the magnitude of the alternating smaller overall stress distribution becomes more uniform. 4 under the conditions of the pouring temperature of 680 ° C, mold preheat temperature of 240 ° C, pressure 80MPa punch injection speed of 0.3m / s, Paul, filling liquid flow velocity uniform filling in good condition, complete filling after the casting temperature distribution uniform; the casting solidification smooth and quickly, in accordance with the order of the design completed solidification; internal quality castings, produce a small amount of defects are concentrated in the gating system can be machined to remove. Huatai hub alternative aluminum alloy, magnesium alloy not only quality can reduce 27%, in terms of structure, the stress distribution is more uniform, more suitable for the movement of the wheels; and wheels manufacturing improvements, making production more simple. The process yield higher than 60%, the production efficiency is also improved, the production cycle of each of the hub is less than 120s.
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