The dashboard is a very important part of a car's interior decoration. Its unique spatial position allows it to perform many operational functions, such as providing the driver with information about the vehicle's driving status for reference; controlling the vehicle's air vents, air conditioning, and other systems to provide the driver with the most comfortable driving environment; and enhancing the driver's overall driving experience. With the development of technology in China, dashboards can now perform even more operational functions and have already been put into practical use. As such, the dashboard must possess sufficient rigidity to minimize component wear during high-speed driving. Additionally, to ensure safe vehicle operation and driver safety, the dashboard must also exhibit excellent adhesion properties. Furthermore, to align the interior design with user aesthetics and preferences, the dashboard's design process must also consider its tactile feel, surface patterns, and color scheme.
injection molding
From the perspective of both plastic rigid instrument panels and foam instrument panels, the injection molding of the frame typically uses a clamping force of 2,000 to 3,000 tons, with the primary materials being PC/ABS or PP+GF. The injection molding process for instrument panels can be broadly categorized into two main types: high-pressure injection molding and low-pressure injection molding. Each process has its own characteristics, and we will analyze both processes below: The characteristics of high-pressure injection molding include: the material is heated by a screw and then injected into a closed mold to form the part.
Positive mold vacuum forming
Positive mold vacuum forming is a manufacturing process used to produce instrument panels, characterized by distinct features. The process primarily involves heating a pad with a patterned surface. When the temperature reaches the same level as that required for stretch forming, the positive mold is lifted, creating a vacuum space between the heated surface and the positive mold. Then, the vacuum suction system is activated, bringing the mold surface into close contact with the cavity of the male mold. After cooling, the mold is removed, and the formed surface is transferred to the next stage of the forming process. Its main advantages include reduced investment in molds, longer service life, high production efficiency, and low equipment costs.
slush molding
The thermoplastic skin has distinct advantages: since its patterned surface is formed during the skin formation process, the consistency of the patterned surface is excellent. During the product design process, localized heating of the mold is effectively managed and controlled, allowing the mold to be more deeply recessed and, in some cases, transformed into a specific negative angle, thereby increasing the design margin of the product model. This enhances the profitability of product design while keeping material costs relatively low. However, it also has corresponding drawbacks: higher mold investment costs and a relatively shorter service life. Large-scale equipment investment is required, and molds need to be continuously cleaned, resulting in extended auxiliary work time.
Negative mold vacuum forming
When manufacturing automotive instrument panels, materials must be processed and shaped. The most commonly used method is the negative mold thermoforming process, which can achieve thermal treatment of the material through in-mold embossing. The negative mold thermoforming technology combines the previous positive mold vacuum thermoforming technology and rotomolding technology. After continuous implementation and research, the negative mold thermoforming technology was developed and has reached a mature level. This method utilizes vacuum suction to fully leverage the roles of the negative mold and heated sheet material, enabling the sheet material to form into shape upon contact with the mold. After thermal processing, as the sheet material cools, it undergoes some contraction, adhering to and bonding with the foam layer to complete the forming process. Compared to traditional forming methods, this technique achieves superior results without causing skin texture stretching. Overall, the quality remains on par with thermoforming technology while retaining its advantages.
Foaming process
In most cases, instrument panels are manufactured through rigorous processing using thermoforming technology, negative molding technology, and PU spraying technology. Furthermore, the subsequent processing operations for instrument panels produced using these methods exhibit a high degree of similarity. Foaming primarily refers to the process of injecting a mixture of polyether and isocyanate between the mold surface and the frame, which results in curing and forms a foam structure between the surface and the frame. This creates a certain degree of connection between the surface and the frame, thereby enhancing the tactile feel of the dashboard and its components.