To address the issue of low efficiency and great subjective influence while the laborer using the oilstone to polish the surface defects of Body-In-White（BIW） parts, this paper proposes a virtual oilstone detection method, and elaborates a data 3D system based on a high-precision 3D scanner data acquisition and automatically analyzes the algorithm and steps of surface defects on automotive panels and BIW. Simulation experiments and online detection experiments of virtual production lines are used to verify the method. The results show that this method can detect BIW surface defects stably and improve the efficiency and accuracy of surface quality detection on the automotive production line.

In order to maximize the efficiency of gear oil and improve the transportation efficiency and economic benefits of users, an on-line monitoring technology of commercial vehicle transmission and drive train oils is developed to monitor the status parameters of gear oil in real time to change oil according to its quality. The test results show that there is a strong linear relationship between dynamic viscosity and kinematic viscosity of gear oil at different temperatures, and dynamic viscosity can replace kinematic viscosity during viscosity calculation. The variation of dielectric constant with temperature, water content, Fe content and acid value content is obvious, which verifies the feasibility of using dielectric constant as a comprehensive evaluation index of gear oil quality, and provides the experimental research basis for multi-parameter online monitoring of gear oil.

At present, the automotive industry mainly through the process monitoring based on coating specifications, as well as the result monitoring based on the final bonding effect to effectively ensure the quality of the coating. In order to improve coating quality detection efficiency, this paper, by learning from to the ultrasonic welding spot nondestructive testing technology, explores the application of ultrasonic phased array technology in the detection of body glue, and proves its feasibility theoretically, Moreover, this paper also uses ultrasonic phased array nondestructive testing instrument for practical application inspection, and finally realizes the nondestructive testing of body glue.

Gap interference exists between the left front combination lamp and the fender of a vehicle model. The design requirement is (1.2±1.0) mm. To ensure the exterior fit meets the design requirements, this paper analyzes the issue from a dimensional perspective. PolyWorks software is used to make dimensional measurements on the beam and side panel assembly, and the headlamp is virtually installed to simulate its posture for verification. This paper also concludes the impact of the parallelism deviation of the integrated bracket mounting surface on the BIW frame on the headlamp’s posture. Combining this with the actual welding process on site, the body fixtures are adjusted and the gap interference issue between the headlamp and the fender is solued ultimately.

In order to improve exterior color quality control and management effect, the management methods of quality control for vehicle exterior color before and after mass production are summarized. Based on the practices, the method combined with color characteristics analysis is proposed. The key characteristic data are analyzed and control standards are established, which aims to improve the recognition efficiency of new vehicle exterior color quality and prevent the occurrence of batch color difference accident.

Using patent analysis methods, this paper analyzes the patent layout of automotive hot stamping dies from the perspectives of patent application trends, regional distribution, and applicants, and taking automotive B-pillar hot stamping dies and automotive longitudinal beam hot stamping dies as examples to interprets important patent technical solutions. From a patent perspective, this paper analyzes the development status of automotive hot stamping die technology from both macro and micro perspectives, and provides reference for subsequent research, development and innovation directions in the field of automotive hot stamping die technology.

This paper focuses on the research, development, application, industrial layout and future trends of hot-formed dual-phase steel ring technology in automotive manufacturing. Initially, the paper provides an overview of the current status of key technologies related to hot-formed dual-phase steel rings, covering material selection and development, application of laser welding technology and optimization of stamping processes. The paper subsequently analyzes the industrial layout of hot-formed dual-phase steel rings, and emphasize the importance of core technological systems in the industrialization process. Finally, the future development direction of this technology is prospected, highlighting the advancements in high performance, lightweight, environmentally friendly and intelligent manufacturing.

In order to evaluate the feasibility of the application of thin Al-Si coated hot formed steel in automobile body, hot stamping test, spot welding test, adhesive matching test and coating test and corrosion resistance test are carried out on single-sided Al-Si coated materials with the weight of 20 g/m² (AS20) and 75 g/m² (AS75). The results show that: AS20 material can use the same heating temperature as the AS75 material, but the heating time is less than the AS75 material; under the optimal heating process, the mechanical properties of the two materials are comparable; the ultimate sharp cold bending angle and maximum force of the AS20 material are higher than those of the AS75 material; the shear strengths of the adhesive joints between the two materials and the structural adhesive currently used in production are comparable, the AS20 material matches well with the structural adhesive currently used in production; the peeling diameter of the fully damaged welding point and the fusion diameter and failure mode of the welding assembly where the two materials are located are equivalent, the spot weldability of the AS20 material is equivalent to that of the AS75 material; the adhesion and corrosion resistance of the electrophoretic paint film of the two materials are comparable. Overall, based on multi-performance comparative evaluation analysis, the main application properties of thin aluminum silicon coated hot formed steel meets the using requirements of OEMs.

In order to solve the problem of the leakage of the flat tube of the all-aluminum low-temperature water tank in the thermal shock test, this article proposes 3 design adjustments, namely, widening the flat tube, changing the O-type collector tube and adding the spacer plate. Finite element analysis software Abaqus is used on the original design scheme and all-aluminum low-temperature water tank under 3 kinds of adjustment scheme for Finite Element Analysis (FEA) analysis, to get the maximum local stress of the flat tube at the leakage area and the maximum plastic strain and its distribution. Thermal shock bench tests are conducted using thermal shock life and the number and location of flat tube leaks as indicators. The results show that the thermal shock life is inversely proportional to the maximum local stress and plastic strain. The location of the leaking flat pipe of the test piece is consistent with the local stress and plastic strain distribution pattern, and the FEA simulation analysis is in good agreement with the test verification. Therefore, in order to extend the thermal shock life of the all-aluminum low temperature water tank, the program sequence is optimized as follows: use of O-type collector tubes, use of narrow flat tubes and use of double bulkheads.

In this research, DC56D+ZM steel plate and DC56D+Z steel plate with coating thickness of 0.7 mm are taken as the research objects. The feasibility and mechanism of Zn-Al-Mg coated steel plate to solve stamping cracking are verified by using friction testing machine for sheet metal forming and stretching ribs, sheet comprehensive forming testing machine, scanning electron microscope, and MTS nanoindentation testing machine. The results show that the surface friction coefficient of the Zn-Al-Mg coating is 25% lower than that of the pure zinc coating. The forming limit performance of Zn-Al-Mg coated steel plates is better than that of pure zinc coated steel plates. Due to the finer grain size and higher hardness of the Zn-Al-Mg coating, the coating has a lower and more stable surface friction coefficient, which can significantly improve the forming performance of the steel plate and effectively improve the stamping cracking problem of automobile parts.

Based on the characteristics of e-ink, flexible segment-code e-ink diaphragm is used to integrate with the trim strip of a vehicle, in order to explore the feasibility of integrating e-ink and interior parts, and the vehicle specification test is conducted. Environmental tests show that the e-ink diaphragm or module can withstand the high and low temperature range of -40~70 ℃, and the e-ink diaphragm will be damaged if the temperature exceeds 70 ℃. The alternating test in the temperature range of -30~85 ℃ is easy to cause the wrinkle or stratification of the multi-layer structure of the module. Therefore, the structure and material of e-ink cannot fully meet the automobile specification test, and further research is needed to identify the application potential of e-ink in automobile interior parts.