When considering materials for car interior parts, especially in applications like 3D printing, it’s essential to understand their limitations, particularly concerning temperature resistance. A common question arises: Can Polylactic Acid (PLA) be used for car interior components? The short answer, especially for parts exposed to sunlight or high temperatures, is generally no.
PLA, while popular in 3D printing for its ease of use and biodegradability, has a significant drawback when it comes to automotive applications: heat sensitivity. Car interiors, particularly dashboards and components near windows, can experience extreme temperature spikes, especially when parked in direct sunlight. Temperatures inside a car can easily exceed 50°C (122°F), even in moderately warm climates.
One user’s experience highlights this issue perfectly. Even for a sun visor hinge pin, a part not in direct sunlight, PLA deformed after just one day in the sun, despite ambient temperatures being around 29°C (85°F). This deformation occurred even though the part was not under significant load, demonstrating PLA’s susceptibility to heat-induced warping. While the example part was eventually replaced with PETG, even PETG showed slight deformation in extreme car heat, indicating the demanding environment of a car interior.
For Car Interior Parts Labeled as critical or load-bearing, or those expected to withstand high temperatures, materials like Nylon (Polyamide, PA), Acrylonitrile Butadiene Styrene (ABS), or high-temperature resistant co-polymers are significantly more suitable. These materials offer superior thermal resistance compared to PLA, ensuring dimensional stability and structural integrity in the harsh conditions of a car interior. Even for non-load bearing components like covers or bushings, opting for a more temperature-resistant material is a safer approach to prevent potential failures or deformations over time.
Technical data sheets from filament manufacturers clearly outline these limitations. For PLA, it’s often stated that it is “not suitable for applications where the printed part is exposed to temperatures higher than 50 °C (122 °F).” Similarly, Nylon, while better than PLA, also has its limits, typically “not suitable for applications where the printed part is exposed to temperatures higher than 80 °C (176 °F).”
To provide a broader perspective, here’s a general temperature guideline for various 3D printing materials in automotive contexts:
- Basic Co-Polymers: ~70 °C (158 °F)
- ABS: ~85 °C (185 °F)
- Enhanced Co-Polymers and ASA: ~100 °C (212 °F)
- Polypropylene (PP): ~105 °C (221 °F)
- Polycarbonate (PC): ~110 °C (230 °F)
In conclusion, while PLA’s ease of printing makes it attractive, its low heat resistance makes it an unreliable choice for most car interior parts labeled for durability and longevity. For components that need to withstand the temperature fluctuations inside a vehicle, especially during hot weather, materials like ABS, Nylon, or other high-temperature co-polymers are far more appropriate, ensuring both functionality and safety.
