For the suspected local flexion injury found during vehicle development, the local flexion was confirmed through comparison of critical flexion stress calculations and measurement of normal deformation, identifying the potential risk of local flexion on durability performance. Through stress measurement, the S-N curve at the notch was modified using the Haywood model. Based on the fatigue damage accumulation model that considers loading sequence and interaction, and the dynamic residual S-N curve, the residual lifespan of the component was calculated, and compared with the experimentally measured residual lifespan to verify the feasibility of the method. Based on the above residual lifespan estimation method, a durability target modification method was proposed, pointing out the shortcomings of this method and engineering solutions.

The continuous improvement of input power and device integration of high-power LED automotive lighting enables the chip junction temperature increase rapidly in a short period of time, reduces its service life and luminous efficiency. Thus improving heat dissipation of LED automotive lighting is a major issue of the present studies. A micro-arc oxidation ceramic coating with a micro-porous structure was prepared on the surface of the aluminum alloy radiator by using micro-arc oxidation surface treatment technology to increase its heat dissipation surface area, the chimney effect produced by the porous structure of the ceramic membrane was used to enhance the convection of heat. This paper utilized ANSYS software to simulate the heat dissipation performance of micro-arc oxidation ceramic coating of high-power LED aluminum alloy radiator, and studied the effect of micro-arc oxidation ceramic coating thickness and porosity on the heat dissipation performance of the radiator. The results show that, when the thickness of the ceramic coating is 28 μm and the porosity is 50.26%, the LED aluminum alloy radiator has the highest thermal conductivity, the smallest thermal resistance value, the best heat dissipation performance.

The hybrid excitation rotor has higher process requirements in the production process. This paper discussed hybrid excitation rotor from 3 perspectives, i.e. how to correctly install the magnetic steel polarity in the manufacturing process, the identification of the magnetic polarity of the excitation coil and slip ring in the process inspection and the effect of different magnetic steel materials on the performance improvement. Through the combination of magnetic steel and claw pole arrays, a dedicated inspection equipment was designed to verify the excitation coil during the inspection process, different materials of magnetic steel were used for performance testing of the generator. The results show that combining the positive and negative poles of the excitation coil with the magnetic steel to form a Haier Beck array can effectively improve the output power of the generator, aluminum iron boron material has a better effect on improving electrical performance compared to ferrite.

An investigation was conducted on the wrinkling of the paint coating on the weld sealant, it was determined that the cause of the wrinkling was poor wetting of the paint on the surface of the sealant. Through verification of material compatibility, influence of plasticizers, baking of sealants, comparison of different formulas of sealants and cross comparison of different film thicknesses in the middle surface coating, it is found that the cause for poor wetting is the thin film thickness of the paint coating. The fluctuation of robot spraying is the main cause for the thin film thickness. However, considering reducing the cost of spare parts and reducing the risk of sagging and foaming, the wrinkling problem was ultimately solved by improving the material’s wettability and an anti-recurrence solution was proposed.

For central black spot defect of molded bearing steel wire, the annealing state and hot-rolled state wire rod samples were tested by means of low acid leaching, metallographic analysis, Scanning Electron Microscopy (SEM) microstructure observation and energy spectrum analysis. By investigation of smelting and rolling process, it is confirmed that the central black spot problem is caused by poor heat preservation of heating agent, causing carbide segregation by element C and Cr concentration at the casting head. According to the causes of the defect, this paper proposed corresponding field process improvement measures, including changing the heating agent to strengthen the heat preservation of the casting head, reduce the pouring superheat, the central black spot defect was finally solved and the qualified rate of the product was increased.

Cr⁶⁺ is widely applied in automotive metal coating and leather, Cr⁶⁺ test is an indispensable index for the test of prohibited substances on automobiles. In order to test Cr⁶⁺ content in the metal coating of automotive materials, a rapid semi-quantitative detection procedure was established by the test strip method. Compared with ultraviolet method and point test method in QC/T 942—2021 Test Methods of Hexavalent Chromium in Automotive Materials, results of the strip test method are basically consistent with traditional qualitative and quantitative test methods. The advantage of strip test method is that the test can be completed within 5 minutes, far less than that of the traditional method that takes 4 to 8 hours. Meanwhile, operation of the test is simple, which saves large amount of test consumables and reduces waste discharge.

This paper studied and demonstrated feasibility of bio-based and degradable Polylactic Acid (PLA) as a substitute of petroleum-based engineering plastics in the fabrication of automotive interior parts. Through 1 year-damp-heat aging test, PLA demonstrated sufficient hydrolysis resistance and weather resistance, meeting the long-time service requirements of automotive interior parts. Through molding and performance verification as a ceilisng lamp shell, PLA was also confirmed to be suitable in automotive interior part design and development.

Due to energy and environmental issues, the global new energy vehicle industry has developed rapidly. High-strength steel, due to its advantages including high strength, excellent machinability, high cost performance ratio, its integrated application in new energy vehicles has become the focus of the industry. Based on the Early Vendor Involvement (EVI) concept, the upstream and downstream industry chain has carried out a number of steel lightweight body projects, such as POSCO PBC-EV, Thyssen In-car, ArcelorMittal S-in motion, Baosteel BCB series and Masteel MCEV, which mainly focus on the body and battery pack and other major components. In the future, with the electrification of the automotive industry, the implementation of energy saving and emission reduction policies and the maturity of key technologies, high-strength steel will play a greater role in the field of automotive lightweight.

Taking the magnesium alloy rear door of passenger car as the research object, the finite element software Comsol Multiphysics was used to establish the galvanic corrosion model of magnesium-steel dissimilar materials and simulate its galvanic corrosion behavior, the corrosion mechanism of magnesium-steel was analyzed by combining the results of electrochemical testing and corrosion morphology. Meanwhile, 4 anti-galvanic corrosion measures were formulated by combining the corrosion mechanism. These 4 anti-corrosion methods, including reducing electrolyte concentration, magnesium alloy surface treatment, reducing cathode area and adding aluminum alloy transition layer between magnesium and steels, can effectively inhibit the galvanic corrosion between magnesium and steels.

The paper described in detail safety standards and risk diagram of automobile manufacturing industry, analyzed the risk level of human-machine interaction station in the welding line, it also introduced the principle and main parameters of safety light curtain, safety laser scanner and other safety equipments. According to the different application scenarios and safety distance calculation formula in safety standards, the paper derived the safety distances of feeding port and the repair station, providing relevant reference for welding line suppliers and automobile manufacturers on the safety construction of human-machine interaction process.