To enable manufacturing enterprises and individuals to choose appropriate Predetermined Time Standards methods, increase the applicability and practicality of Predetermined Time Standards methods application process, this paper analyzed the methods of Modular Arrangement of Predetermined Time Standard (MOD), Methods-Time Measurement-1 (MTM-1), Methods-Time Measurement - Universal Analysis System (MTM-UAS) in terms of time accuracy, analysis efficiency, improvement supportability effect, application threshold and application standardization, the paper also provided reference suggestions for method selection and application.

In the production of a vehicle, the painting shrinkage appeared near the liftgate hinge gasket. This defect occurred frequently and needed to be polished and repaired on site, which greatly affected the production efficiency. The pollutant was determined to be methyl cyclosiloxane by gas chromatography, mass spectrometry and other tests. The cause is that when the silicone rubber gasket is baked in the paint workshop, small molecules of methyl cyclosiloxane are precipitated, which leads to paint pollution. According to this problem, the liftgate hinge gasket was changed from silicone rubber to ethylene propylene diene monomer rubber, which completely solved the problem of paint pollution.

The hot-rolled wire rods of 6056 aluminum alloy were solution treated at 470~600 ℃, water quenched and artificially aged. The effects of different solution temperatures on the mechanical properties, fracture morphology, metallographic and intergranular corrosion resistance of Al-Mg-Si-Cu aluminum alloy were investigated by tensile property test at ambient temperature, intergranular corrosion resistance test, combined with optical microscopy, scanning electron microscopy and energy spectrum analysis. The results show that Mg₂Si in the microstructure of 6056 aluminum alloy dissolves more fully into the matrix as the solid solution temperature increases, while the undissolved iron-rich and copper-rich phases do not show significant changes. The tensile strength increases with the increase of solid solution temperature, reaching a peak around 540 ℃. When the solid solution temperature increases to 570 ℃ and 600 ℃, the strength changes slightly, but the elongation first increases and then decreases with the increase of solution temperature. The intergranular corrosion resistance decreases with the increase of solid solution temperature.

In order to study the characteristics of residual stress distribution on DP980 high-strength steel treated by Laser Peening (LP), a finite element analysis model was established to analyze the influence of different LP times on the stress distribution both on the surface and in the depth of the material. Additionally, strenuous tests with different LP times were carried out, and the residual stress of samples was tested to verify the consistency of experiment and simulation results. By comparing the surface roughness of the samples before and after LP, it indicates that plastic deformation occurs on the sample surface, and a uniform residual stress distribution is generated on the surface after LP. In order to achieve the internal stress balance, a low-amplitude tensile stress is induced at the core of the sample along the depth direction. With the increase of LP times, the residual stress induced on the surface of sample rises, and a deeper influence layer is generated. In fact, the residual stress induced by LP on the material surface increases the micro-crack closure force inside the parts and then postpones the crack growth rate, thus improves the service life and reliability of parts effectively.

In order to address the issue of corrosion in the manufacturing and storage process of die cast aluminum alloy parts without coating on the surface, this article analyzed the corrosion mechanism and cause of die cast aluminum alloy parts, and elaborated on an anti-rust scheme suitable for die cast aluminum alloy, test and application research on anti-rust materials and processes were also carried out. Corresponding rust prevention measures were adopted for each link in the plan, including the use of water-based rust prevention materials and vapor phase rust prevention materials. After laboratory and vehicle verification, this anti-rust technology can effectively prevent corrosion in the manufacturing, storage, transportation, assembly and other processes of die cast aluminum alloy parts, and systematically solve the corrosion problem of die cast aluminum alloy parts.

This paper explored the influence of different preparation time and closed stage time on the air quality test results inside the car in HJ/T 400-2007 “Method for Determination of Volatile Organic Compounds and Aldehydes and Ketones in the Car”. The experimental results show that when the preparation time increases from 6h to 32h, the concentration of VOC substances in the air quality of the vehicle generally shows a decreasing trend. The initial concentrations of formaldehyde, benzene, ethylbenzene and styrene were low, and reached equilibrium rapidly with the extension of preparation time. With the extension of the blocking time from 16h to 32h, the concentration of styrene, ethylbenzene and benzene changed little, and the concentration of toluene, xylene, formaldehyde, acetaldehyde and TVOC increased gradually.

The traditional industrial robot rolling method relies heavily on manual adjustment, resulting in low debugging efficiency and difficult quality control. To address this issue, this article explored the application of industrial robot adaptive edge rolling tools in edge rolling pressing process and its effect on improving edge rolling quality. The effectiveness of industrial robot adaptive rolling tools in adaptively adjusting rolling pressure was verified through experiments, which can significantly improve production debugging efficiency. In addition, the article also discussed the effects of speed and pressure on the rolling quality, as well as how to ensure the safety of equipment operation through monitoring alarms. Research has shown that adaptive rolling systems can significantly improve the surface quality of rolling and pressing.

To address the issue of difficulty in designing and producing aluminum plate rear door inner plate caused by poor formability and ductility of aluminum plate material, complex shape of rear door inner plate, this paper introduced the simulation analysis of the formability of aluminum plate back door inner plates theoretically based on AutoForm finite element software. Through simulation analysis of different solutions, the final forming solution was determined which guided on-site production, and was verified in on-site debugging.

To address the issue of flanging cracking of automotive high-strength steel longitudinal beam, this paper analyzed the mechanical properties of parts and cause of cracking. Using empirical method to modify the die to prevent crack source generation and crack expanding has certain effect, but cannot eliminate cracking. Formability analysis of flanging process was carried out by using AutoForm software simulation, which proved the empirical method, the effect of process gap, and the consistency between simulation and reality. Through simulation, a better form of process gap was found. The simulation results were applied to die modification, which eliminated flanging cracking, reduced the die changing time, shortened the optimization cycle and reduced cost.

To guide the design of car seats and save development time, this paper studied the effects of residual stress and plastic deformation generated after sheet metal parts stamping on the crash simulation of car seat based on one-step stamping, and investigated the automatic processing method of stamping process. Stamping simulation of sheet metal parts was conducted through the Radioss_One_Step module of Altair HyperWorks software. The program was optimized by TCL/TK and Python language, to achieve the automatic batch processing of stamping simulation of all sheet metal parts of seat, meanwhile, the stamping results was automatically mapped to crash model. This paper took the driver’s seat of a vehicle as research object to perform crash simulation and physical test of the 50th percentile male dummy. It is found that the rear impact simulation with the stamping results is closer to the physical test, the simulation is more accurate. Moreover, the optimized batch program can save more than 90% of the working time.