Study Of Isothermal Forging Process For Rare Earth Magnesium Alloy Bracket With Reinforcement

Production trend in the modern high-end manufacturing industry is moving towardlightweight materials and structures. With excellent mechanical properties at roomtemperature and high temperature, strong anti-temperature creep resistance and corrosionresistance rare earth magnesium alloy is an ideal material with which to produce lightweightcomponents. Because of high reliability, the whole complex structure with reinforcement isthe ideal structure to achieve components lightweight. Isothermal forging is the ideal processto achieve near net forming, making it possible to achieve complicated forgings withreinforcement forming at the same time. Using experimental design, numerical simulation,parameter optimization, and physical experimentation, this study examined the isothermalforging process for a rare earth magnesium alloy bracket with reinforcement.Die design is the key to the isothermal forging process of forging with reinforcement.According to the structural characteristics of bracket, die structure parameters were selectedas design variables. Deformation uniformity and forming load were selected as objectivefunctions; fractional factorial design was used to opt three key factors that had a significanteffect on response, including radius at rectangular column R2, draft angle at rib die, andradius at rib die R3. The selected variables were further optimized by central composite design,which was based on the response surface method. The regression equation between responseand the design variables was fit, then the best parameter combination for die was obtained:scilicet radius at rectangular column R2of4.74mm, draft angle at rib die of4.55°, andradius at rib die R3of4.25mm.Process parameters are important factors for bracket shaped by isothermal forming.Deformation temperature (T), deformation rate (v), and friction coefficient (μ) were selected as design variables, which influenced the forming process of the bracket. Deformationuniformity and forming load was selected as the objective function. Variables were thenoptimized using Box-Behnken design. The mathematical regression model for deformationuniformity and forming load was analyzed, and the optimum technological parametercombination for isothermal forming of bracket was obtained: deformation temperature at480°C, strain rate at1.25mm·s-1, and friction coefficient at0.3.The die was designed and manufactured by appropriate materials according to theoptimized parameters of die structure and forming technology. The isothermal formingprocess of the bracket was formulated, and physical experimentation was implemented toshape a bracket which met the requirements.