For a car, people pay more and more attention to interior design while pursuing appearance and power. The interior not only reflects the function of the interior space of the car, but also makes the passengers feel comfortable, easy to operate, and visually beautiful. Therefore, the interior has become an important battlefield for the competition of different brands of cars today.
Automotive interior parts mainly include: steering wheel, compartment partition, door inner panel, instrument panel, airbag cover, seat armrest, carpet pad, door handle, cup holder, decorative strip, ceiling, sun visor, side window frost guard, glove box and cover, sound-absorbing lining and other components. The materials used play a key role in the lightweight, economy and comfort of interior parts. Among them, plastics have become the mainstream of interior parts, accounting for more than 80%.
Automotive interior parts have increasingly put forward higher requirements for the materials used. From the research situation of various countries, the development of interior plastics mainly presents the following trends:
1. Energy saving and weight reduction
The weight reduction can be understood from three aspects: low density, thin-walling and replacing steel with plastic. Low density is easier to understand. For example, low-density materials are used in door panels and columns, and micro-cellular foam materials are used in instrument panels and door panels. Thin-walling refers to reducing the thickness of the wall by improving the performance of plastics, creating weight reduction. The use of plastic instead of steel is suitable for the following situations: one is when the structure of the component is complex and the mechanical properties are required to be high, high-strength plastic materials are used to replace the metal materials traditionally used in this field, such as long fiber and carbon fiber modification. The other is to select high-performance materials that meet the requirements for the realization of certain functional needs.
2. Green and healthy
The importance of low VOC is increasing day by day, and materials such as spray-free plastics and bio-plastics will be more widely used due to their low VOC properties.
The spray-free technology is a one-time injection molding to form the final product, eliminating the need for surface pretreatment, painting, drying and other work, reducing costs by about 40%. Spray-free materials have good chemical resistance and scratch resistance, can be recycled and reused, and have low comprehensive use costs. In recent years, they have become the trend in the auto parts injection molding industry.
Since bio-plastics use low-toxicity and low-harm renewable raw materials, they will greatly reduce the volatilization of VOC in the car after they are made into automotive interior parts. In addition, it can be decomposed, which is conducive to subsequent recycling and is a more environmentally friendly plastic variety. Compared with pure polypropylene products, it has the characteristics of light weight, high hardness, long service life and excellent mechanical properties. Since it is filled with biomass, it can reduce the consumption of petroleum resources, be more environmentally friendly, and have higher flame retardant, and can reduce the weight of parts by about 20%.
3. Safety
Interior parts are not only required to be comfortable and beautiful, but also to protect the safety of passengers. A large number of elastic modified plastics and foamed plastics that can absorb energy are used to reduce the damage to the human body caused by collisions and improve the safety factor. Pay attention to the selection of flame-retardant and flame-retardant materials, and halogen-free flame-retardant materials reduce the odor of the air in the car. In addition, it is necessary to consider the strength, heat resistance, wear resistance, etc. of the material, all based on the premise of protecting the safety of drivers and passengers.
4. Materials general utilization
In order to effectively utilize energy and raw materials and reduce the cost of automobiles, the materials used in different types of car interior parts can be attributed to several common material suppliers. Maintain a balance between low cost and high quality through a modular material supply chain, specialized production, and improved technical content.
5. Composite materials
Parts using composite materials in automobiles are basically composed of skin (plastic, fabric, leather), sound and vibration damping (foam or fiber) and skeleton. This form of parts not only meets certain functions, but also makes people feel comfortable and beautiful , is one of the important development directions of automotive interior parts.
6. Quality upscale
The end users of the interior are the drivers and passengers. Therefore, when selecting materials and designing, we must adhere to the human-oriented design principle, and consider the occupants' vision, touch, hearing and taste. And with the differentiated needs of different auto OEMs for brand positioning, more and more attention is paid to the characteristics related to sensory experience. For example, Volkswagen's odor standard PV3900 requires the odor level of interior plastic materials to be below level 3, and some auto OEMs even use odor as the basis for selecting material suppliers. The interior creates a sense of comfort and luxury, which is the only manufacturing concept for high-end cars.
