For the differences between BIW aluminum parts joining technology routes in Germany and Japan, the article adopted the research method of typical and benchmarking analysis to describe the principle, forming process and process characteristics of aluminum parts joining technologies of VW AG and Toyota Company, and compared the process technology routes of VW and Toyota from 4 aspects of lightweight, quality, efficiency and cost, and formed a comparative analysis table for the types of BIW aluminum parts and joining processes of VW and Toyota. It is concluded in this article that the types of BIW aluminum parts, joining processes and investment of VW are more than those of Toyota’s, which all meet their quality requirements. The article proposed that FAW should draw on the application experience of aluminum joining technologies of VW and Toyota.

The self piercing riveting & bonding composite connection point with aluminum plate was taken as the research object. In the early stage, through the dynamic tensile test and CAE simulation modeling calibration of the connection point under 3 working conditions of tension shear, tear and forward tension, the parameters in the constitutive relationship of CAE simulation model were accurately obtained. Finally, the comparative verification test of CAE collision simulation and high-speed impact was carried out for T-shaped components with multiple working conditions, CAE simulation accurately predicted and realized the failure of the connection point, and the simulation accuracy reached 95.9%. It accurately characterized the deformation and failure behavior of the riveted-bonded composite connection point under mixed complex working conditions, which has high practicability in the CAE simulation of vehicle collision.

In order to improve the efficiency of the electric drive system for electric vehicles, this article summarized the solutions to improve the efficiency of the electric drive system in motor design, material selection, process assembly and other aspects. In the motor design, motor suitable for the electric vehicle was selected, and the control algorithm was optimized; in terms of materials, copper wires, silicon steel materials and high-frequency materials with high performance were selected; in process assembly, the application of flat wire winding process can improve the torque and efficiency of the motor, the core and stacking process were optimized to reduce the motor iron loss. The efficiency of motor drive system for electric vehicles can be improved by increasing the system output efficiency and reducing various losses.

The Galvannealed(GA)-coated sheets are subjected to cold rolling deformation, and the changes in the morphology, element distribution and corrosion resistance of the GA coating at different reduction rates are explored. The results show that the original coating before rolling is mainly composed of δ(FeZn7) and Γ(FeZn10) phases, and a free Zn layer with loose distributed holes is found on the surface of the coating. The holes are deformed into needle shape along the rolling direction, and the density gradually decreases. When the reduction rate is greater than 40%, the needle-like micro-holes disappears. With the increase of cold rolling reduction rate, the thickness of the coating layer decreases continuously, and the hardness of the coating layer and the substrate increases. When the reduction ratio is larger, the interface presents a zigzag shape. The change of reduction rate has little effect on the distribution of Zn and Fe elements, and there is an iron-rich diffusion layer at the interface between the coating and the substrate. When the reduction rate is greater than 20%, the coating is broken to a certain extent, and a small amount of O element begins to exist at the interface of the coating and the substrate. The weight loss of GA coated sheet under corrosion tends to be gentle with the increase of time, and the difference of loss weight between different reduction rates is small, and the coating after rolling still protects the substrate well.

This paper described the phenomenon of punching delamination of hot-rolled steel plate 700L for frame side rails and its harm. Through macro and micro observation, combined with the blanking process principle, the factors of material, process and mechanism that lead to delamination in punching were analyzed. It is believed that severe plastic deformation during punching leads to serious fibrosis of the structure, and the fibrous structure delaminates or breaks under the action of shear stress and normal stress, forming a competitive mechanism with the generation and expansion of main cracks in the tear band. If the delamination and fracture of the fiber occur later than the crack of the tear band, the delamination or serrated fracture on the surface of the punched hole can be prevented. Using Theory of Inventive Problem Solving(TRIZ) theory, the prestressed punching process is designed and developed, which not only ensures the integrity of the punched hole surface, but also ensures the punch life.

Based on the Dongfeng vehicle project, the conformal cooling channel consistent of the circuit board shell was established. The effect of the conformal cooling scheme was analyzed by MoldFlow and ANSYS, and compared with the traditional cooling scheme. Finally, the metal 3D printing process was used to fabricate the mold kernel and the cooling channel, which was verified on the injection mold. The results show that the conformal cooling scheme greatly improves the injection efficiency and reduces the deformation of the product.

To effectively solve the knotty problem regarding anti-corrosion design, management and control during vehicle development, this paper applied the Concurrent engineering concept of integrated design of material, structure, process and performance, and decomposed the vehicle anti-corrosion characteristics into subsystem anti-corrosion characteristics and parts performance index, then evaluated the achievement of indicators and formulated development plans, controlled comprehensively the whole anti-corrosion design process using diversified technical methods and cross departmental linkage and coordination mechanisms, boosted the coordinated development of corrosion characteristics, aging and other related characteristics of paint coated parts and improvement of anti-corrosion technological standards, promoted the anti-corrosion design capability enhancement of vehicle system, eventually upgraded vehicle durability steadily.

Projection welding of M12 ring convex welding nut and 2.5 mm thick plate has the defect of faulty welding, using energy storage welding machine in place of power frequency convex welding machine can solve the defect of faulty welding. There is an optimal combination of welding voltage, tempering voltage and welding pressure in the welding parameters of the energy storage welder. The orthogonal test is suitable for optimizing the optimal welding parameters. The optimized parameters (welding voltage 650 V, tempering voltage 650 V, welding pressure 16 kN) were used for test welding to obtain a convex welding joint with ejection force of 33.55 kN, which was greater than the target value of 16 kN. The high strength joining between ring convex welding nut and thick plate is realized, proving that the capacitor energy storage welding machine has the advantages of energy saving, high efficiency and stable welding quality, which is suitable for the welding between large nut sizing over M10 and thick plate.

In view of the situation that existing CAPP system for engine valve is difficult to directly group and establish a database problem for the valve parts made by the enterprise, a valve part grouping program was developed based on grouping technology. For the problem that CAPP system characteristic cannot indicate clearly after matching the positions needing modification for the existing process files, the relationship between valve part characteristic and machining was simulated based on numerical control technology, and a new matching program of valve parts characteristic was developed.

Due to the effect of internal stress, cold stamped fender has springback deformation, resulting in dimensional deviation. In order to optimize the size of finished parts, CAE simulation tool is used to compensate the springback of parts in the early stamping process design. Taking the steel fender as an example, this paper elaborates a springback compensation method based on the analysis results of CAE simulation, which corrects the position that the size does not meet the standards on the basis of perfecting the simulation file, setting the scale, optimizing the process method, and positioning the parts of the fender. This method is verified by actual production inspection that the dimensional accuracy of the parts is effectively improved.