Based on the complex structure of new energy vehicles, this paper studies the baking simulation technology. In order to solve the baking problems caused by the application of new materials to the coating process and avoid the baking defects in vehicle model launch and production, baking simulation software is used to simulate the coating electrophoresis baking. The paper performs synchronous engineering analysis, guides and evaluates the scheme of drying room renovation, and provides feasibility assessment and parametric suggestions.

With the increasing prevalence of small batch and multi variety production modes in the automotive manufacturing industry, engine companies have developed a large number of modular subpackage scenarios to address the differences in the number of workstations, personnel configuration, and process layout between different engines under this mode, and further enhance the efficiency, flexibility, and scalability of production lines. This paper takes an engine assembly production line as an example to compare the concepts and characteristics of 2 modes, namely, online subpackage and centralized subpackage. The design parameters of the 2 subpackage modes are explained, and a mathematical model of process quota is proposed. MATLAB is utilized to simulate the relationship between process quota and output in the centralized subpackage mode, and the critical conditions for lean management of the 2 subpackage modes are obtained to improve lean control capabilities and provide reference for subpackage planning of related production lines.

To enhance the management level of Perfluoroalkyl and Polyfluoroalkyl Substances (PFAS) in China’s automotive industry, this paper studies the production, usage, and management of PFAS such as Perfluorooctane Sulfonate (PFOS), Perfluorooctanoic Acid (PFOA), and Perfluorohexane Sulfonic Acid (PFHxS) in China’s automotive industry. It further analyzes the current challenges faced by the industry, including the lagging PFAS control regulations and the lack of targeted industry standards. Additionally, this paper proposes governance recommendations to promote PFAS management in China.

To explore the surface technology for corrosion protection of magnesium alloys, biomimetic anticorrosion surfaces such as superhydrophobic and slippery surfaces have received extensive attention in the past decade. This paper summarizes typical bionic superhydrophobic anticorrosion methods for preparing magnesium alloy surface, including electrochemical deposition, chemical etching, anodic oxidation, laser etching, spraying and so on, and discusses the characteristics of each preparation method and the research progress of bioinspired surface anticorrosion of magnesium alloy. In addition, the paper also summarizes the commonly used methods for preparing anticorrosion slippery surface of magnesium alloy, which means constructing structured substrate first and then injecting lubricant, and one-step spraying method. The research progress of slippery anticorrosion surface of magnesium alloy is discussed. Finally, the challenges and future development directions of superhydrophobic and slippery surfaces of magnesium alloys are summarized.

In order to improve veatherstrip odor of vehicles, this paper studies automotive weatherstrip odor test method and evaluation standard, compares the test standard of different OEMs and world mainstream organizations, analyzes and summarizes the current standard system. Moreover, the causes of weatherstrip odor and improvement measures are discussed. This paper also proposes improvement schemes from perspectives of material selection and optimization in the mixing process, use of water-based paint in the production process, and appropriate increase of storage temperature in the storage process.

In order to constantly improve the manufacturing flexibility of Body-In-White production lines and optimize the usable load capacity of industrial robots in welding shops, the paper elaborates the optimization techniques of serial robot tool system under the multi-constraints of engineering retrofit design. In the design of welding robotic non-standardized tool, such as gripper, welding gun and riveting gun, while considering its function structure, reliability and economy, measures are implemented comprehensively according to the process design scheme from dimensions including machine, material, method, measurement and environment, which are verified through simulation analysis and actual measurement, so as to achieve the technical goal of the robotic tool load optimization. Moreover, the practical effects of the optimization techniques in three typical cases are illustrated.

To investigate the effect of electrical parameters and electrolyte concentration on the properties of Micro-Arc Oxidation (MAO) coatings on magnesium alloys, Mg-Zn series magnesium alloys are used as the research substrate. Silicate-based electrolyte is employed to prepare MAO coatings on the surface of the magnesium alloy. By varying the electrical parameters and electrolyte concentration, this paper studies the influence of different parameters on the performance of the MAO coatings. The results show that with the increase of voltage and duty cycle, and the decrease of frequency, the energy provided increases, leading to an accelerated coating growth rate and an increase in coating thickness. With the increase in current density, the coating thickness initially increases and then decreases, as the effect of current density on coating thickness depends on the growth rate and reaction time. The coating thickness is directly proportional to the electrolyte concentration; however, excessively high electrolyte concentrations can cause localized ablation, resulting in coating detachment. The MAO coatings significantly enhance the corrosion resistance of the magnesium alloy, and both increased coating thickness and reduced pore size can improve the corrosion resistance. MAO samples immersed in a 3.5% sodium chloride solution for 120 h exhibits a corrosion rate of 0.24 mm/a. A composite coating of MAO followed by electrophoretic deposition is prepared on the surface of a magnesium alloy automotive battery case. The MAO coating thickness is approximately 13.7 μm, and the electrophoretic coating thickness is about 25 μm, withstanding a neutral salt spray test for 720 h.

In order to achieve intelligent predication of magnesium alloy die-casting parts, reduce offline labor inspection cost, and improve intelligent level of magnesium alloy die-casting industry, this paper collects big data on “process parameters-quality parameters” of large thin-walled magnesium alloy castings, and uses random forest model to establish the relationship between process parameters and the types of defects in castings, and analyzes the effect of long-tailed distribution of labels in the industrial data on the predictive performance of machine learning models. Then the “Random Downsampling + SMOTE Over-sampling” algorithm is emptoyed to balance the distribution of the data set. Finally, an accurate prediction model with an accuracy of 89.54%, an area under ROC curve of 0.983 8, and an average true rate of 87.65% are obtained, which achieves a precise detection of a small number of defective samples, and obtains the ranking of the importance of key process parameters for magnesium alloy casting.

This study investigates the tensile properties, bending properties, hydrogen embrittlement sensitivity, spot welding performance, and coating corrosion resistance of Al-Si coated thermoformed steel based on vanadium and niobium composite microalloy under typical hot forming processes. The results indicate that under heating temperature of 930 ℃, heating time of 300 s and holding time of 10 s, the experimental material achieves a tensile strength of 2 000 MPa and extreme tip cold bending angle is greater than 50°, demonstrating a favorable combination of strength and toughness. The mechanical properties exhibit significant anisotropy, with a notable improvement in toughness after baking at 170 ℃ for 20 minutes. The strength and ductility parameters display varying strain rate sensitivities across different strain rates ranging from 0.1 ~ 500 s^-1. In a four-point bending test at 100% yield strength in an air environment, the hot-formed material show no cracks or fractures after 300 h, indicating excellent resistance to hydrogen embrittlement. Additionally, the spot welding performance and coating corrosion resistance of the experimental material meet application requirements.

To address the issue of electrochemical corrosion of steel-aluminum hybrid vehicle body, especially galvanic corrosion, corrosion test of aluminum alloy is studied to explore the influence of different steel-aluminum joining material and method, different forming process on aluminum alloy corrosion. The results show that the corrosion grade of the bolted samples is higher than that of SPR riveting due to the double effects of galvanic corrosion and crevice corrosion, whereas corrosion resistance of cast aluminum alloy is obviously lower than that of extruded profile due to segregation of components.