Choosing suitable plastic materials for automotive exterior parts requires comprehensive consideration of component function, environmental resistance, safety performance, and cost control. Different parts have different performance requirements due to varying usage scenarios.
Core Material Selection Principles
Impact Resistance: Exterior parts are frequently subjected to stone impacts and low-speed scratches, necessitating the use of high-toughness materials such as PP+EPDM and TPO to ensure they are not prone to cracking.
Weather Resistance: Long-term exposure to sun and rain requires priority given to materials resistant to UV aging, such as ASA and PC/ABS alloys, to prevent fading and embrittlement.
Moldability and Precision: Complex curved surfaces (such as bumpers and grilles) rely on injection molding processes, requiring materials with good flowability and low shrinkage to ensure dimensional stability.
Lightweight Requirements: Plastics have a density only 1/8 to 1/4 that of metals, helping to reduce fuel consumption or improve the range of electric vehicles, making them a mainstream choice.
Environmental Protection and Recyclability: Materials such as PP and TPE have a recyclability rate exceeding 95%, aligning with the sustainable development trend of the automotive industry.
Practical Material Selection Strategy
For everyday family vehicles: Prioritize mature materials like PP and ABS, which offer high cost-effectiveness and low maintenance/replacement costs.
For high-end/new energy vehicles: Consider heat- and weather-resistant materials such as PC/ABS, ASA, or modified PBT to improve overall vehicle quality and durability.
For off-road or commercial applications: Emphasize impact resistance and tolerance to extreme environments; reinforced PP or TPU composite materials are recommended, such as modified PP+EPDM+TD specifically for mudguards.
