Everything you make with a 3D printer, from a figurine to a modular part, will be as durable as the filament you use. Use a weaker material with low tensile strength and the part will be relatively fragile and/or fragile. Of course, it depends on what you’re creating, but if you need something stronger, it makes sense to go for stronger filament materials. But what are they? What Types of 3D Printer Filaments Can Make the Strongest Parts?
The short answer, based solely on tensile strength, is carbon fiber nylon (PA12 CF), a composite material, followed by polycarbonate (PC). But since tensile strength alone doesn’t determine strength and other factors matter, it makes sense to take a closer look. They may be the strongest, but that doesn’t mean they’re ideal for every job.
Carbon fiber nylon has a rated tensile strength of 70 megapascals (MPa) or approximately 10,152 pounds per square inch (PSI). It is an excellent choice for durable prints and parts because it benefits from the strength properties of nylon but has the lightness and strength of carbon fiber. However, because small pieces of carbon fiber are embedded in the filament and are abrasive, this can cause significant wear, even on modern printers. Additionally, while the material resists warping during printing and cooling, its rigidity also makes it brittle. So it’s not ideal for parts that need to be shock resistant or will be subject to vibration and other notable applications. Carbon fiber nylon is also not very flexible. You can really see that, although it is very durable, carbon fiber filament is not the best choice for all jobs.
Polycarbonate is another good choice for durable prints
With a tensile strength of around 67 MPa (9,800 PSI), polycarbonate filament is second only to nylon composite. It also has some properties that composite does not have. It is strong, durable and has high impact resistance. Both materials can withstand heat of up to 300 degrees Fahrenheit, meaning they will retain their shape quite well even in extreme temperatures. But this also means that both, including polycarbonate, require higher printing temperatures. You’ll need a printer that can handle nozzle temperatures of 500 to 572 Fahrenheit and heated bed temperatures between 176 and 230 Fahrenheit.
Polycarbonate’s incredible strength and durability comes from its slight flexibility, as it is much less brittle and has much better impact resistance than nylon. However, it is only available in a limited selection of colors (usually transparent, black or white). The higher temperatures required almost eliminate the formation of complex or highly detailed shapes and edges. It is ideal for practical pieces and simple shapes, not for objects with a lot of fine detail, such as toys or figurines with complex elements. You’ll also likely need sturdy printing tools at your workstation to work with and shape the polycarbonate material once it’s finished drying.
Polycarbonate is a good choice for individual parts and mechanics, hinges, components, molds, enclosures and multi-part assembly projects. In comparison, carbon fiber nylon can make similar modular parts, like camera mounts, spool rollers, latches, and parts with less detail. There are other unique 3D printer filaments, but none as strong as carbon fiber or polycarbonate.
Where to turn when you need more flexibility?
Strength is an interesting word to wrap your head around when it comes to printing filaments because it can mean a lot of different things. Do you want the piece to withstand physical pressure? Do you want it to withstand harsh impacts or high temperatures? Or do you want it to resist breakage? These questions refer to different types of strength: physical strength versus flexibility. For flexibility, thermoplastic polyurethane (TPU) is the best choice.
It’s hard in a different way, and because it’s so flexible, it’s not easy to break. It has a tensile strength of between 20 and 100 MPa, but even at the upper end of this range the material is neither rigid nor stiff, so it is not suitable for parts, pieces or components for which this property is integral. Additionally, it does not require high temperatures to print or form, nor does it have extreme developing properties. You can use virtually any printer, but it will take longer to print because it forms at colder temperatures and requires slower print speeds. TPU is a good choice for clothing and shoes, accessories, cases and other components such as watch bands, cable ties or small tools.
With materials ranging from nylon to carbon fiber to TPU, understanding how to care for the filament will go a long way toward successful prints. Curate it appropriately, use high-quality sources, and follow the other tricks of the trade.
