| Oil consumption reduction and performance enhancement have become the development trend of road vehicles, especially of motorcycles. Due to their nature of high-speed motion and rotation, weight reduction of the wheels is the most efficient way to reduce the oil consumption, to improve the accelerating and braking performance, to enhance the riding comfort of a road vehicle. Naturally, use of light weight materials on the wheels is the most straight-forward way to achieve the goal.Mg alloys have different mechanical and processing properties in comparison with most widely used steel and aluminum alloys. Consequently, Mg alloys cannot be directly used on the commercial wheels before the structure of the wheels is redesigned in accordance with the service condition and compliant to the processing characteristics of the materials in order to ensure the performance and safety.To promote a scientific use of Mg alloys on wheels of road vehicles, the present study was devoted to numerical analyses of stress and strain distributions in a Jialin wheel under identical service condition, structural redesign to reduce the service fatigue stress. Then, mass and heat transfer during die-filling, temperature distribution and solidification, and their effects on the formation of the processing defects during the squeeze casting were analyzed with a commercial software to optimize the quality of Mg-alloy wheels manufactured. According to the results obtained, squeeze casting mould was designed. The main results were highlighted as follows:①Use of tilted spoke and the small transition radius gives rise to a stress concentration at transition segments of the wheel.②In accordance with the fact of lower fatigue strength of Mg alloy, the tilt angle of the spoke and the radius of the transition curves were modified in structure optimization, leading to a reduction of the peak service stress from 37.9MPa to 23.68MPa to ensure the wheel's service life.③With the optimized processing parameters of 680℃pouring temperature, 0.15m/s injection speed, 250℃mold preheating temperature and 80MPa holding pressure, the die filling is uniform, the distribution in the casting is comparatively uniform, solidification process is stable and in a expected progressive mode. The processing defects mainly concentrated in the gating system, which can be removed by following-up machining. ④The mold consisting of mold framework, moving and fixed mold blocks, moving and fixed mold bed plate, sprue spreader, demolding mechanism and pullback mechanism is designed. The assembly process was carried out with virtue reality. An entire 3D mold assembly diagram was completed in the actual manufacturing order. Currently, the mold is in manufacturing in Chongqing SinoST Co. Ltd. according to the design of the present study.
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