近年、自動車産業の急速な発展に伴い、人々のカーシートに対するさまざまな要求も向上し続けており、カーシートの軽量化、多機能化、環境快適性、安全性は人々のカーシートに対する基本的なニーズであり、これらの側面は徐々にカーシートの発展の主な方向になってきています。

長繊維複合材料は樹脂と長繊維複合材料で構成されており、高強度、低密度、生産時間が短い、成形しやすいなどのさまざまな特性を備えており、現在の自動車シートの開発動向に適しているため、自動車業界では徐々に自動車シートの好ましい材料になってきました。

チャイルドシートの概要

車のシートは主に、シートカバー、シートピロー、シートフォーム、シートスケルトンの 4 つの部分で構成されています。さらに、市場のさまざまなニーズに応じて、一部のシートにはアームレスト、ウエストサポート、マッサージ関連の快適コンポーネントも付いています。一部のシートには、カップホルダーや引き出しなどの他の収納機能もあります。

現在、消費者は自動車シートのデザインに対して、軽量、快適性、安全性などさまざまな面を求めるようになっています。しかし、従来のシートの主材料は金属材料がほとんどで、金属の密度が高く、構造とデザインの最適化だけで自動車シートの軽量化を向上する開発余地は限られていました。

長繊維強化複合材は優れた機械的特性を持ち、大幅な軽量化効果が得られるため、自動車分野では、ほとんどの単純で重要でない部品だけでなく、シートスケルトンやフロントセグメントモジュールなど、一部の複雑な形状の機能部品にも徐々に応用されています。

自動車の軽量化の重要性

車の軽量化は、車の安全性能と強度を保証できるという前提のもと、車全体の重量を最大限に軽減し、車のパワーを高め、排出量と燃料消費量を削減することを意味します。

関連テストによると、自動車の燃料量は自動車自体の重量と最も直接的な関係があり、自動車の質量が1kg減少するごとに、100キロメートルあたりの燃料消費量を0.2～0.8L削減でき、通常は元の消費量の約4％～5％になります。したがって、現段階では、環境保護と省エネを徐々に重視する自動車開発の背景の下、現代の自動車の軽量化は、その設計と製造プロセスにおいて大きな意義を持っています。

車のシートは、車内の最も重要な部品の1つです。調査によると、車のシートの重量は車体全体の1％から2％を占めています。車のシートが車体の総重量に占める割合は小さいですが、車の最も重要な部品の1つとして、車全体の軽量化プロセスへの貢献は過小評価できません。

Car seat is one of the more complicated parts in the whole car design process. The design process of car seats must be considered from many aspects, such as safety, aesthetic shape, functional diversity and comfort. Only under the premise of meeting the requirements of traditional car seats can the lightweight design of car seats be implemented. While reducing the weight of the car seat, the basic performance of the car seat must be guaranteed, especially the safety of the seat. Under the influence of these requirements, the lightweight design of car seats becomes more challenging and more worthy of research.

Application of long fiber composites in automotive field

Long fiber composite materials have also developed rapidly with the rapid development of industrial economy. At this stage, long fiber composites have become one of the fastest growing industries in the reinforced plastics industry.

The application proportion of long fiber composite materials in the automotive field is large, accounting for about 33% of the total consumption, and will continue to grow with the development of the automotive industry. At present, long fiber composite materials are widely used in automotive interior, functional parts and structural parts. The use of long fiber composite materials to replace the traditional metal materials can reduce the weight of automobiles, and simplify the production process and modular production.

General Motors, one of the largest automobile manufacturers in the world, has applied long glass fiber composite materials to the cargo board of sports vehicles and light trucks. Ford is one of many leaders in the application of composite materials. Its cars use fiber-reinforced sheet plastic as a material for body insulation panels. In 2011, PP-LGF50 material was used in the driving seat of a certain model of car produced by BMW in Germany, which reduced the mass of the car seat by 63% and also increased the service life of the car seat.

The application of long fiber composite material in automobile seat

1) Improve the service life and safety of the seat
The fatigue resistance of long fiber composite material is higher and it has more matrix. Its fatigue fracture does not burst out suddenly, but slowly spreads from the matrix to the collective interface and the fiber.

Therefore, people can detect the damage of long fiber composite materials in advance, and take corresponding remedial measures in time, effectively improving the service life of the seat.

In addition to fatigue resistance, long fiber composite materials also have stable safety, if overloaded parts made of this material, the role of the car seat will not immediately disappear, but first break a small number of fibers. The load is then quickly redistributed and transferred to the undamaged fibers, so that the entire component will not be knocked down by the heavy load in a short time.

2) Reduce the vibration amplitude of the seat
There is a large damping between the interface of the long fiber composite and the matrix, and it has good vibration damping performance. When the same size and shape of long fiber composite material and metal material are tested under the same conditions, the decay time of the former is shorter than that of the latter. Therefore, the car seat using long fiber composite material effectively reduces the vibration frequency and duration of the seat.

3) Reduce seat costs
No chemical reaction is required in the processing of long fiber composite materials: the reinforced fiber is directly extruded in a predetermined direction and arranged on the matrix at the same time to form a layup structure and press it in a high-speed hydraulic press. This method not only saves the cost of buying semi-finished products and reduces the manufacturing cost, but also guarantees the fiber length and optimizes the mechanical properties of the component.

In addition, the matrix is combined with the fiber, and then the mold is heated and cured, it can be made of long fiber composite parts, and the matrix is transformed from a fluid to a solid during the production process, so the car seat made of long fiber composite materials is not easy to crack.

4) Reduce the damage of the seat at high temperature
Long fiber composite materials can achieve high temperature resistance under normal conditions. When the ordinary aluminum alloy is at high temperature, its elastic modulus will be greatly reduced. However, under the same conditions, the elastic modulus and strength of the composite reinforced with long fiber materials can remain unchanged. Because the long fiber composite has a small thermal conductivity, its high temperature resistance is better. The application of long fiber composite materials to car seats can effectively reduce the damage degree of car seats under high temperature conditions.

5) Maintain the stability of various performance of the seat
The characteristics of long fiber composites are high specific stiffness and high specific strength, and their properties have a wide range of variation. According to the different fiber material, fiber content and laying direction, the designed product strength index, flame retardant performance and elastic modulus are also different. When the long fiber composite material is stretched in one direction under a certain layup mode, the material can also be extended perpendicular to the stretching direction, which is completely different from the commonly used materials. In the design process of car seats, materials that are easy to design and can maintain stable performance should be selected. Long fiber composite materials can be flexibly designed in different shapes while maintaining the stability of all aspects of their performance.

Conclusion

車の座席は車の積載能力を担うため、交通事故が発生したときに車内の乗員の安全を確保する上で非常に重要な役割を果たします。

したがって、軽量、快適性、安全性の向上は、自動車シートの発展における避けられない傾向です。長繊維複合材料はさまざまな優れた性能を備えており、自動車シートの品質を向上させながら品質を下げ、さまざまな性能を向上させると同時にコストを削減します。

自動車産業の急速な発展と長繊維複合材料開発の技術レベルの継続的な向上により、自動車シートにおける長繊維複合材料の応用展望はますます広がることが分かります。