3D printing has evolved significantly, with different types of filaments available for various applications. PLA (Polylactic Acid) is one of the most commonly used filaments due to its ease of use and affordability. However, for those needing enhanced strength and durability, carbon fiber filament has become an attractive option. But is carbon fiber filament really stronger than PLA? In this article, we will compare their properties, strengths, and applications to determine which filament is best suited for specific uses.
What is PLA Filament?
PLA (Polylactic Acid) is a biodegradable thermoplastic derived from renewable resources such as corn starch and sugarcane. It is widely used in 3D printing due to its low printing temperature, minimal warping, and eco-friendliness.
Key Properties of PLA:
- Ease of Printing: Requires lower temperatures and minimal post-processing.
- Biodegradable: Made from natural sources and decomposes over time.
- Brittle: Less impact-resistant compared to other filaments.
- Limited Heat Resistance: Softens at around 60°C, making it unsuitable for high-temperature environments.
- Affordable: One of the most budget-friendly filaments available.
What is Carbon Fiber Filament?
Carbon fiber filament is a composite material that consists of a base thermoplastic (such as PLA, PETG, or Nylon) reinforced with short carbon fiber strands. This reinforcement enhances the strength, stiffness, and durability of the material, making it suitable for demanding applications.
Key Properties of Carbon Fiber Filament:
- Increased Strength and Stiffness: More rigid and durable than regular PLA.
- Higher Heat Resistance: Withstands higher temperatures depending on the base material.
- Lower Weight: Offers a high strength-to-weight ratio.
- Reduced Flexibility: Less flexible due to the carbon fiber content.
- Requires Specialized Nozzles: Can wear out standard brass nozzles quickly.
Strength Comparison: Carbon Fiber vs. PLA
Tensile Strength
Tensile strength refers to the maximum amount of stress a material can withstand before breaking.
- PLA: Has a tensile strength of around 60 MPa, making it relatively strong but brittle.
- Carbon Fiber PLA: Can reach tensile strengths of 80 MPa or more, making it stronger and more durable.
Impact Resistance
Impact resistance measures how well a material can absorb sudden shocks or forces.
- PLA: Brittle and prone to cracking under impact.
- Carbon Fiber PLA: More resistant to impacts, but still somewhat brittle compared to flexible filaments like TPU.
Flexural Strength and Stiffness
Flexural strength determines how much a material can bend before breaking.
- PLA: Offers decent flexural strength but is prone to deformation under pressure.
- Carbon Fiber PLA: Much stiffer due to the carbon reinforcement, reducing flexibility but increasing durability.
Heat Resistance
- PLA: Softens at around 60°C, making it unsuitable for high-heat applications.
- Carbon Fiber PLA: Has improved heat resistance depending on the base polymer (PETG or Nylon-based carbon fiber filaments perform even better in high temperatures).
Applications of PLA vs. Carbon Fiber Filament
When to Use PLA:
- Prototyping and hobbyist projects.
- Low-stress applications such as figurines and decorative items.
- Educational models and beginner-friendly prints.
When to Use Carbon Fiber Filament:
- Functional parts requiring durability, such as drone frames and automotive components.
- Aerospace and industrial applications due to its strength-to-weight ratio.
- High-stress applications where rigidity is essential.
Printing Considerations
Ease of Printing
- PLA: Beginner-friendly with minimal warping and easy adhesion.
- Carbon Fiber PLA: Requires an all-metal hotend, hardened nozzle (e.g., stainless steel or ruby-tipped), and careful bed adhesion management.
Cost
- PLA: One of the cheapest filaments available.
- Carbon Fiber PLA: More expensive due to the added reinforcement and specialized manufacturing process.
Conclusion
While carbon fiber filament is indeed stronger than standard PLA, it is not always the best choice for every project. PLA is ideal for beginners, prototypes, and low-stress applications due to its affordability and ease of use. However, when strength, stiffness, and durability are priorities, carbon fiber filament is a superior option. Before choosing a filament, consider your specific project requirements, budget, and 3D printer compatibility.