Numerical Simulation And Experimental Research Of Laser Welding Of Steel/aluminum Hybrid Car Body Structures

The lightweight of car body is an important role in the development of lightweight vehicles. The new concept of steel-aluminum hybrid car body structures can better take into account all aspects of lightweight requirements and it represents the latest trends for the future development of car body structures. Welding of aluminum alloy with steel is a difficult work due to the formation of brittle intermetallic compounds, and the use of laser welding technology by strictly control the welding parameters is a possible solution to surpass this problem. The laser welding input parameters such as laser power and welding speed have always played a very important role in welding aluminum alloy with steel process,especially in determining the quality of the weld joint. The finite element simulations are carried out using commercial FE software SYSWELD.The Taguchi method with L16 orthogonal array is used to perform the numerical experiment design. The optimal welding parameter for multi-objectives is obtained using multi signal to noise ratio (MS/NR).Furthermore, the method of response surface methodology (RSM) is used for regression modeling to establish the relationship between the laser welding input parameters like laser power, welding speed and beam angle and for optimizing the process parameters. Based on the numerical experiment confirmation test, the results show that the proposed method can be effectively applied to estimate the mechanical resistance and von Mises stress which can improve the quality of the dissimilar materials weld joints.