This paper conducted an in-depth study on the internal cavity corrosion of new energy control modules. The paper firstly analyzed the key factors contributing to corrosion in the cooling system cavity of conventional fuel vehicles. Through a plasma concentration orthogonal test, this study simulated the equivalent ion concentration of the cooling medium to identify the influential corrosion factors. Subsequently, by comparing the corrosion rates of aluminum substrates under different corrosive media, this paper demonstrated the applicability of traditional test methods to new energy control systems. A cavity blockage test was designed to verify the functional failure of the cooling system under affected conditions caused by corrosion. Finally, based on the investigation of internal cavity corrosion in new energy control systems, evaluation criteria for conducting internal cavity corrosion test within the company were developed.

PA66 material has good heat resistance and is widely used in heat-resistant parts of lamps. However, because it is prone to thermo-oxidative decomposition, the small molecular substances decomposed are easy to form fog deposits, which affect the appearance, performance and service life of lamps. Therefore, the study of low-volatile PA66 composites is an urgent issue to be solved. This paper investigated the effects of antioxidants, molecular sieves, PA10T, processing technology and other factors on the volatility of PA66 composites under thermo-oxidative aging, and analyzed the main components of volatiles. It concluded that the copper salt (0.5 wt%)+ PA10T (30 wt%)+double vacuum scheme had better fogging, and proved to meet the requirements.

Based on the Gissmo damage failure model, the failure parameters of 6082 automotive aluminum alloy profile were obtained by numerical parameter inverse method. The reasonability of the Gissmo damage failure model of 6082 aluminum alloy was verified by the quasi-static three-point bending test of the aluminum alloy impact beam. Firstly, the hardening curve of the 6082 material was obtained by quasi-static uniaxial tensile test, and the curve was extrapolated by Swift-Hockett-Sherby (SHS) law. Secondly, quasi-static tests (shear, uniaxial, central hole, notch, three-point bending, cupping) under various stress states were carried out, and Gissmo failure parameters were obtained by numerical inversion of test combined with simulation. Finally, the quasi-static three-point bending test of 6082 aluminum alloy impact beam was designed to verify the reasonability of Gissmo model. The test result shows that the Gissmo damage failure model of 6082 aluminum alloy proposed in this research, including hardening curve, failure strain curve, instability curve and mesh-size regulation curve, can predict the failure behavior of 6082 impact beam.

In order to achieve traceability management of quality issues in stamping parts, the structure, principles, and advantages and disadvantages of mold mechanical coding technology and equipment laser coding technology were analyzed. Mechanical coding is installed on the mold, and online replacement results in production line shutdown. The coding time is accurate to weeks; Laser coding is integrated with the production line, without the need for stopping the production line to change labels, and the coding time is accurate to the parts.Different coding methods were selected according to different application conditions to meet the precise quality traceability control of stamping parts from single batch to single piece. At the same time, through digital means, various fields of coding information are connected, achieving tracking from stamping profession to vehicle quality traceability information binding.

For the problems of flange cracking for cross member of steel H420LAD, the stamping simulation of cross member was performed, the scheme was evaluated on type of flange, major and minor stain, paths of strain. The results show that minor stain was the main parameters of parts flanging and cracking, the decrease of minor strain was beneficial to eliminating flange cracking, increasing the plastic strain was the direction of material optimization. 2 schemes to stamp processing were proposed and simulated, the results show that after optimization of the gaps between die and punch, the distances between the blocks for flanging and the punch, the forming safety margin was increased from 0% to 4.49%, the edge quality of part was improved slightly. The optimization of blank was carried out, the process of pre-flanging was changed to drawing, process of trimming was added, the forming safety margin was increased from 0% to 16.44%, and the qualified rate of the parts is 100%.

At present, most of the powertrains of medium and large luxury cars adopt the form of longitudinal engine rear-drive. Based on the assembly of a luxury brand vertical engine structure in the engine pre-assembly line of the assembly workshop, a specially designed engine carrier lifting fixture was used to realize the process installation of the parts. The lifting fixture was used to simultaneously lift the engine and transmission as well as the front axle assembly on the pre-assembly line, and automatically move the suspended integrated lifting fixture assembly and the workpiece on the pre-assembly line by carrying lifting fixture, thus completing the process installation of the parts. This paper discussed the application advantages and functional characteristics of this engine pre-assembly line process planning scheme and engine carrier lifting fixture for simultaneous suspension of multiple large mass parts, then introduced cases of lifting fixuture optimization.

A Ls-dyna software based self-piercing riveting joint simulation method for vehicle crashworthiness analysis of was proposed in this research. Method of solving failure parameters for self-piercing riveting joint was studied based on the combination of finite element analysis and test in different forced states, thus improving simulation calculation efficiency while ensuring simulation accuracy. Firstly, a refined simulation model for riveted joints was established based on experimental design, afterwards, a simplified simulation model was established using *CONSTRAINED_SPR2. Using the extracted values from experimental and refined simulation results as simplified parameter inputs can greatly improve the calculation speed of the vehicle crash crashworthiness model. Through this study, it is shown that this method can achieve a simulation accuracy of over 90% for the peak failure force of the self-piercing riveting joint through calibration with experimental results, and can be applied to crashworthiness analysis of complete vehicle model.

To improve the pickling and passivation process quality of aluminum part before body welding, this paper introduced the pickling and passivation process and common quality problems of aluminum parts before welding, as well as the pickling and passivation process and wastewater treatment technology. The paper provided effective solutions based on practical production. Electrophoresis film quality defects of aluminum parts caused by residual oil were eliminated by optimizing degreasing process. Combined with electrophoresis coating quality and the surface resistance of aluminum, Ti-Zr coating process can’t be found on the surface of aluminum parts before pickling and passivation.

In order to find the source of formaldehyde emission from automobile parts at high temperature, the research team, by simulating the formaldehyde emission test of the automobile parts under high temperature conditions, used the spectrophotometric method to test 13 kinds of materials commonly used in the car, analyzed the formaldehyde emission amount of different materials under the same conditions, and combined the use of different materials in the car to confirm the main source of formaldehyde emission in the car, so as to provide direction of improvement for auto parts manufacturers.

After the vehicle abuse road test, the eccentric bolt connecting spring swing arm and subframe rotates mainly because the flange surface of the bolt is convex, the friction on the flange surface is uneven, and the friction coefficient does not meet the standard requirements (standard value: 0.08~016, measured value: head friction coefficient is 0.25~0.27, and the total friction coefficient is 0.18~0.20). The friction surface of flange is line contact. Compared with the surface contact, this kind of bolt has poor anti-loose and anti-rotation performance. Improve the flatness of the bolt flange surface and the uniformity of the friction surface by the following measures: reducing the step height at the hexagon connection of bolts (from 3.2~3.25 mm to 3.1~3.15 mm), increasing the hole diameter of gasket before riveting (from 13.85~13.9 mm to 14.3~14.35 mm) and making the gasket into an opposite angle before riveting (0.5°~1°). The friction coefficient of optimized bolt is qualified, and there is no abnormal rotation failure after the vehicle abuse road test.