Hot Deformation Process And Performance Of Aluminum Alloy Control Arm For Automobile

Automotive lightweight is an inevitable trend of automotive industry development.Because aluminum alloys have high specific strength and specific rigidity and good formability and corrosion resistance,replacing steel with aluminum has become one of the important ways for automotive lightweight.The control arm is an important safety component in the automotive suspension system.Its performance directly affects the performance of the car,so it has strict requirements on its strength and fatigue resistance.The study object of this paper is the two-point control arm of 6082 aluminum alloy,whose complex shape,forging process parameters and heat treatment parameters will affect the performance of the control arm.The main purpose of this study is to formulate a reasonable forging process plan and heat treatment plan for 6082 aluminum alloy control arms.In this paper,the method of combining numerical simulation and process test is used to study the effect of hot forming process parameters on product organization and performance from two aspects of forging and heat treatment,so as to formulate a reasonable forging and heat treatment process plan.According to the characteristics of aluminum alloy control arm forgings,we set the forging process as cross wedge rolling,bending,secondary heating,pre-forging and final forging.First,the numerical simulation software is used to study the influence of the die temperature on the forging temperature field.The die temperature is set to 200?,300?,and 400?,respectively.The simulation results show that for every 100? increase in the die temperature,the forging temperature increases by about 5?.And through the process test,it is found that as the die temperature increases,the mechanical properties of the forgings are improved,and the coarse grain condition of the forgings is also improved.The method of numerical simulation is used to study the effect of the blank transfer time on the temperature field of the forgings.The transfer time of the blanks,after every process,is set to 10s,20s,and 30s respectively.The simulation results show that with each increase of the transfer time of the blank,the forging temperature field decreases by about 15?.And through the process test,it is found that as the blank transfer time increases by 10s,the mechanical properties of the forgings will decrease,and the thickness of coarse layer will also increase.After the forging,the forgings are subjected to T6 heat treatment,T5 heat treatment and residual temperature heat treatment.The test results show that the heat treatment process has a great influence on the mechanical properties of forgings and the condition of coarse grain.The forgings after the solid solution quenching+aging treatment have good mechanical properties,but the coarse grain is difficult to control;the mechanical properties of the forged pieces after T5 heat treatment are quite different from those of T6,but the coarse grains are in good condition,with only a few appearing.The mechanical properties and coarse grain condition of forgings treated with residual temperature quenching and aging treatment are not much different from T6 heat treatment,but the treatment time of solid solution can be shortened and production efficiency can be improved.Through numerical simulation and practical experiment,this paper proves that forging process parameters and heat treatment process plan have great influence on the performance of forgings.Reasonable forging process parameters and heat treatment process parameters can effectively reduce production costs and improve production efficiency while obtaining products with good performance.