低延展性铝合金自冲铆成形工艺试验及仿真分析OA

Based on the BBD response surface method,a statics experimental study on the self-piercing riveted joint of AA2024 aluminum alloy with low ductility was carried out,and AL1420 and AA5182 aluminum alloys were taken as the test reference objects.A joint connection quality prediction model for analyzing the influence of the processing parameters,including sheet elongation,rivet hardness and riveting speed on the response value was established,and internal lock length and tensile shear strength as response values.Meanwhile,the finite element simulation model for self-piercing riveting joint was established to analyze the stress and strain distribution characteristics of the joint mechanical locking area and the cracking reasons of the self-piercing riveting forming bottom sheet of low ductility aluminum alloy.The experimental results show that the error between the predicted and the experimental value is less than 9.0%.The sheet elongation has the most significant effect on the joint connection quality(internal locking length and tensile and shear strength),which shows a tendency of increasing first and decreasing.The sheet elongation and rivet hardness have the most prominent effect on the joint connection quality in the interaction.At the sheet elongations of 12%-18%,the rivet hardness of 340-360 HV,the joint connection quality is the best,but for low ductility aluminum alloy,the joint connection quality is the best when choosing rivets with high hardness.The simulated analysis results are shown that:the peak stress of the plate appears at the corner of the concave mold cam and near the rivet foot.With the decreasing of sheet elongation,the stress value in the stress concentration area of the sheet increases and the crack tendency increases.