The stamping process and function of body covering parts
The key technical link in the simulation analysis of the stamping process of car body coverings is that the production process of coverings is generally divided into processes such as deep drawing, edge cutting, and flanging. Stamping simulation can be applied to any process in the stamping production of coverings For a simulated process, it is necessary to trace its manufacturing process and convert product design information into relevant information about intermediate processes. This is one of the technical difficulties in the simulation of cover stamping forming. The second difficulty is to determine the reasonable geometric shapes of punch, die, binder, and drawbead, especially the smooth transition of multiple three-dimensional surfaces in these shapes Stamping forming of covering parts is a plastic deformation process with large deflection and deformation, involving the plastic flow, plasticity, rebound, wrinkling, and cracking of metal plates under complex stress states of deep drawing and bending Meanwhile, the stamping process is also a complex multi-body contact mechanics analysis problem In order to accurately simulate and analyze the stamping process, it also involves the study of material parameters, the determination of static and dynamic friction coefficients and viscosity coefficients in the multi-body friction lubrication model, as well as the determination of the force motion curve of the press, the loading method and curve of the blank holder force, and the arrangement of the deep drawing ribs.
In the simulation analysis of stamping forming of car body panels, materials are one of the simulation objects. In simulation research and production applications, the influence of material models (types) and material properties on stamping forming, as well as the relationship between material structure, sheet metal process, and material forming performance parameters, are studied
Many researchers have paid attention to issues such as relationships.
There are two types of materials involved in the stamping process, namely mold materials and blank materials (also known as sheet metal or billet) In order to analyze the mechanical properties during the stamping process, a mechanical model of the material, abbreviated as the material model, is established Compared with sheet metal, stamping die materials have high hardness and rigidity, and it can be considered that the die is non deformable during the stamping process. In stamping simulation analysis, rigid body material models are generally used to simulate die materials. This is a simple material model that does not require consideration of its stress-strain situation.
The body is one of the four major assemblies of a car, and with the continuous expansion of automotive services and increasingly diverse and personalized demands, body design has gradually taken the lead. According to statistics, the body mass of buses, sedans, and most cars accounts for about 40% to 60% of the total vehicle mass; The weight of the truck body accounts for about 16% to 30% of the total vehicle weight; The manufacturing cost of each vehicle model's body as a percentage of the total vehicle is even slightly higher than the upper limit given above. From the perspectives of energy and material conservation, the potential of body design is great.
The practice of automobile production fully demonstrates that the development of vehicle production capacity depends on the production capacity of the body; The new generation of automobiles also largely depends on the body of the car; When the basic vehicle models reach saturation, only relying on body modifications or alterations can open up sales.
The main function of a vehicle body is to carry passengers or goods, acting as a temporary shelter or mobile warehouse. It is a mobile building that is limited by quality and space, and its detailed function varies depending on the vehicle. In terms of sedan body, its functions can be summarized into the following five points: 1) realizing the overall vehicle functions; 2) Provide passengers with a comfortable riding environment; 3) Provide protection for passengers; 4) Reduce air resistance; 5) Enhance the aesthetics of the sedan.
The characteristics of the car body are mainly reflected in several aspects, such as the wide coverage of the car body, the variety of car body materials, and the development of car body styling. The structural characteristics of the car body mainly lie in the thin materials, large dimensions, complex shapes, and mostly free-form surfaces of the various components that make up the exterior of the car body (i.e. the so-called body coverings).
