Based on the experience of commissioning automated assembly technology for multiple models in a front-wheel drive vehicle project, the paper summarizes the general commissioning processes and methods related to Best-fit technology, its input-output advantages, and quality status evaluation. This paper also emphatically introduces the practical application of this technology in the production of new vehicle models, providing forward-thinking insights and standardized approaches for BIW panel parts of new projects to ensure assembly dimensions.

In order to improve quality and performance of battery material, and address the battery safety issue, the contents of nickel, cobalt and manganese elements in the cathode materials of ternary lithium batteries are accurately determined by Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES), and the uncertainty in the measurement process is systematically evaluated according to the standard of JJF 1059.1—2012 “Evaluation and Representation of Measurement Uncertainty”. The uncertainty factors that may be introduced in each part of the test are deeply analyzed, and these uncertainties are carefully quantified and calculated. When the nickel content of the sample is 5.521 μg/mL, the extended uncertainty is U₉₅(Ni)=0.013 1 mg/kg. When the content of cobalt is 3.566 μg/mL, the extended uncertainty is U₉₅(Co)=0.011 8 mg/kg; when the manganese content is 2.102 μg/mL, the extended uncertainty is U₉₅(Mn)=0.013 1 mg/kg. Finally, the synthetic uncertainty of nickel is u(Ni)=0.006 6 mg/kg, the extended uncertainty of cobalt is u(Co)=0.005 9 mg/kg, and the extended uncertainty of manganese is u(Mn)=0.006 5 mg/kg.

For the issue of PMMA toughened material which easily produces mold fouling and affects the manufacturing of automotive lighting, this paper proposes a mold fouling collection device which can be used to observe the precipitation of the mold fouling at different shear rates and examine composition of mold fouling by the method of Py-GCMS. In addition, 2 toughened PMMA materials are selected to study the influence of the material characteristics on the mold fouling by differential scanning calorimetry and thermogravimetric analysis. The results show that from a technological point of view the higher the shear rate due to shear heating, the higher the temperature, the more the mold fouling precipitates are produced; from the perspective of the material formulation, the lower the glass transition temperature, the lower the temperature rise under the same shear, the less the mold fouling is produced.

The method of laser offset is used to simulate the deviation of edge trimming precision of aluminum alloy door parts. Taking the laser focus on the lap joint edge as a reference, the effect of the different offset distance, namely trimming deviation of parts on weld forming and properties is investigated. The results show that the weld seam surface forming and cross section morphology change with different trimming deviations. In term of weld seam forming, when the trimming deviation of the part gradually increases from -1.0 mm to +1.0 mm (the direction in which the trimming of the part is away from the laser spot and exposes the lower plate of the lap joint to the laser is defined as negative, and the opposite direction is defined as positive), the surface of the weld seam gradually becomes full. In term of weld seam mechanical properties, when the trimming deviation of the part is within the range of -0.5 mm to +1.0 mm, the change of the trimming deviation has little effect on the mechanical properties of the weld seam, and when the trimming deviation is -1.0 mm, the tensile strength of the weld joint is significantly reduced. Therefore, in order to ensure the forming and mechanical properties of the welding seam on the aluminum alloy door, the trimming deviation of parts should be ensured in the range of -0.5 mm to +1.0 mm during the trial production process.

To explore the application value of topological optimization design method based on additive manufacturing in the field of commercial vehicle lightweighting, this paper proposes 2 types of optimization schemes through the optimization process of topological calculation, geometric reconstruction and print simulation analysis taking the commercial vehicle post processor bracket as the test object, and the Selective Laser Melting (SLM) process is utilized to complete the physical additive manufacturing. Finally, both schemes pass the verification of the 8 000 km enhanced road bench test, the results indicate that the topology optimization design method based on additive manufacturing fulfills the design and performance requirements.

In order to rapidly select the best lubricating grease for vehicles in different conditions, 4 actual vehicle working conditions are simulated including normal driving, heavy load, climbing and high speed using a four-ball machine with the wear diameter of the measured sample as evaluation index. Combined with droplet point, evaporation loss and oxidation stability, the performance of 4 long-life composite lithium based grease is studied, and the best choice of lubricating grease under different using scenarios are summarized as well.

At present, 6016 aluminum alloy automotive sheet has attracted much attention for its excellent performance. This paper discusses the whole process production technology of 6016 aluminum alloy automobile sheet, including chemical composition, melting and casting, rolling, heat treatment, chemical treatment and electrostatic oiling, and emphatically expounds the basic principle, technical status and research progress of each production process. It finally prospects the development directions of 6016 aluminum alloy automobile sheet production technology in aspects of chemical composition design, new melting and casting technology, short process rolling technology, heat treatment technology, chemical treatment technology and key equipment localization.

Cooling performance of coolants with 6 different types and contents of additives is studied through cooling rate experiments. The result shows that the cooling performance of the coolants with the nonionic additive is the best, followed by the coolants with the mixed additive, and the coolants with the ionic additive exhibits the worst cooling performance. The lower the additive content, the better the cooling performance of the coolant. The cooling performance of coolant A containing 0.11% non-ionic addifive by mass is the best, with the shortest time corresponding to the probe temperature reaching 200 ℃, which is 6.1 s and the maximum cooling rate reaches 60 ℃/s.

In order to analyze the influence of the adhesive layer on the surface quality during the manufacturing process of the sandwich structure, modeling and analysis are carried out in the finite element analysis software ABAQUS with PMMA as the main research object. During the hot-pressing manufacturing process of the sandwich structure, the influence of the adhesive on the surface quality is studied through the 2 processes of heating and pressurization. The results show that when only the heating process is considered, due to the viscoelasticity of the adhesive, PMMA will become softer as the temperature rises, which will lead to an increase in the surface waviness; when only the pressurization process is considered, the viscoelasticity has almost no effect on the surface waviness. When the hot-pressing is coupled, the surface waviness will be greater than that when only heating or pressurization is considered alone; the softer the adhesive, the greater the surface waviness. By adjusting the characteristics of the adhesive, the surface quality of the sandwich structure can be effectively controlled, thereby improving the overall quality of the product.

In this study, the silicone-oil damper of a heavy-duty diesel engine is taken as the research object, and a linear cumulative damage model of the silicone-oil damper is developed by taking silicone-oil deterioration as a damage parameter. Based on the results of mixed cycle and load cycle durability engine bench tests, the life model of the damper is calibrated. Combined with the measured road load spectrum, the service life of the silicone-oil damper in actual usage scenarios has been predicted. The results show that under the working condition of the tractor, the predicted life of the M60 damper based on mixed cycle and load cycle tests is 1.425 million km and 2.896 million km, respectively, both of which meet the requirements for engine life mileage.