Automotive plastic parts can be roughly divided into functional parts and structural parts according to their main uses.
Functional parts are independent parts that use some special physical and chemical properties of materials, such as plastic oil-impregnated bearings.
Structural parts are covering parts, mounting parts, shells, beams, etc. that work with the mechanical properties of the applied materials.
However, this division is also relative, often taking into account both or focusing on one of them. Functional parts or functional parts usually meet certain structural requirements, such as plastic folding, plastic leaf springs, etc., on the basis of ensuring the required physical and chemical properties. The structural parts must also meet the necessary physical performance requirements under the premise of ensuring certain mechanical properties. For example, the bumper of a car has to withstand the impact of the whole vehicle on the concrete wall at a speed of 8km/h. It also has good weather resistance; the overall plastic instrument panel has a large load due to the installation of many internal and external parts (automobile instruments, etc.) on it. It not only requires accurate dimensions, good rigidity, high thermal deformation temperature, resistance to exposure and creeping It becomes smaller and has to withstand the impact of a spherical pendulum with a diameter of 165mm and a mass of 6.8kg at a speed of 25km/h, so as to absorb enough energy without being damaged; it is also like an engine cooling fan, which has blades under high-temperature baking and strong shocks. The root has to withstand the pulling force formed by the huge centrifugal force of 6000r/min.
In short. Although the functional requirements of various structural parts are very different, it is bound to be able to put forward the most basic thermal and mechanical performance indexes that can reflect the properties of the component materials that the polymer materials must meet. With the development of the plastics industry, the emergence of various new resins and various high-performance materials obtained through modification methods such as alloys, blends, and composites will inevitably be able to meet the needs of the automotive industry for functional plastic parts and structural plastic parts and their The various comprehensive performance index requirements put forward by the materials used gradually expand the application range of plastics in automobiles.