Simulation Study On Forging Process Of Aluminum Alloy Control Arm

Under the dual background of increasing vehicle usage and increasing light weight,6000 series aluminum alloys are widely used in automotive parts due to their excellent comprehensive performance,and gradually transform from non-structural parts to structural parts.The control arm is one of the key components of the automotive suspension system and has high requirements for stiffness,strength and service life.However,due to the defects of folding,coarse crystal and over-burning,the complex die forgings of aluminum alloy are constrained,which restricts the extensive use of aluminum alloy forgings on automobile structural parts.In this paper,the finite element simulation and experimental method are combined to simulate the forging process of aluminum alloy control arm,and a reasonable forming process is designed.The control arm forgings with good microstructure and mechanical properties are successfully prepared.The main research results of the thesis are as follows:According to the structural characteristics of the control arm,a composite forging method of roll forging and die forging is designed.The roll forging process was rationally designed using two-pass roll forging and elliptical-circular groove systems.The multi-field simulation and analysis of the velocity field,temperature field and stress-strain field in the forging process verified the rationality of the forging process design.The designed process can be used to obtain forgings without defects such as folding and flow.The effects of process parameters such as initial forging temperature,roll forging speed,mold preheating temperature and friction coefficient on the forming of roll forgings were analyzed.The optimum process parameters for the roll forging process were as follows: initial forging temperature 530~540 ?,mold preheating The temperature was 350 ° C,and the roll forging speed was 30 r/min.The effect of different initial forging temperature on the metallographic structure of the roll forgings was studied.When the initial forging temperature was 535 ? and above,the roll forgings with fine and uniform microstructure could be obtained.When the initial forging temperature was below 500 ?,the grain size of the roll forgings was coarse..The grain coarsening mechanism is the secondary recrystallization of the critically deformed grains.Through the field experiment,the forgings with optimized process parameters were preliminarily tested,and the grain size distribution of the final forgings before and after optimization was compared.It was found that the optimized forging process greatly improved the coarse grain defects of the aluminum alloy forgings and optimized the yield strength of the forged parts.The tensile strength and the tensile strength increased by 7% and 8.2%,respectively,and the forgings with acceptable microstructure and mechanical properties were obtained.The research results of this paper provide theoretical basis and technical support for the forging of aluminum alloy complex structural parts,which has important guiding significance for actual production.