PLA, ABS, and nylon are three of the most popular 3D printing materials. All can be extruded on basic 3D printers and, at around $20 per spool, they are among the most affordable filaments available today. Most people focus on the PLA vs ABS debate, but Nylon is a valuable third entrant with different material properties.
PLA and ABS are both thermoplastics. PLA is stronger and stiffer than ABS, but poor heat-resistance properties means PLA is mostly a hobbyist material. ABS is weaker and less rigid, but also tougher and lighter, making it a better plastic for prototyping applications.
Enter nylon, a flexible plastic that injects a new set of filament properties into the mix, featuring greater chemical resistance and toughness compared to PLA and ABS, but also reduced strength.
This post compares PLA vs ABS and now nylon, and then details how one of these thermoplastics has been augmented to serve a wider range of manufacturing applications. Plus, a bonus exploration of Onyx filament.
PLA is a user-friendly thermoplastic with a higher strength and stiffness than both ABS and nylon. With a low melting temperature and minimal warping, PLA is one of the easiest materials to 3D print successfully. Unfortunately, its low melting point also causes it to lose virtually all stiffness and strength at temperatures above 50 degrees Celsius. In addition, PLA is brittle, leading to parts with poor durability and impact resistance.
Although PLA is the strongest of these three plastics, its poor chemical and heat resistance force it into almost exclusively hobbyist applications.
ABS, while weaker and less rigid than PLA, is a tougher, lighter filament more suitable for some applications beyond purely hobbyist. ABS is a bit more durable, is about 25% lighter, and has four times higher impact resistance. ABS does require more effort to print than PLA because it’s more heat resistant and prone to warping. This calls for a heated bed and an extruder that is 40-50 degrees Celsius hotter. ABS, while by no means a heat resistant plastic, has superior heat deflection temperature compared to PLA and nylon.
The improved durability over PLA lends ABS to some more practical applications, such as prototyping and low-stress end-use parts.
Nylon is a flexible, durable plastic with less strength and stiffness than both PLA and ABS. Its malleability lends it much more toughness than the other two, however, with an impact resistance ten times that of ABS. Nylon also boasts a good chemical resistance, which opens the possibility to more industrial applications. As with ABS, nylon requires extra care to print; it needs to be extruded at high temperatures and, due to its tendency to soak up moisture from the air, must be kept in a dry box.
Nylon is tougher and more resistant to chemicals than ABS and PLA, but its low strength and stiffness keep it from being widely used in the manufacturing industry. As a result, advancements in 3D printing materials has introduced nylon-fiber mixtures, opening the door to accessible industrial 3D printing.
Filled Nylon and Onyx
Filled nylon is a mixture of nylon with small particles of a stronger material such as fiberglass or carbon fiber. These mixtures preserve the favorable properties of nylon while adding considerable strength and stiffness. Markforged’s Onyx filament is an example of one of these mixtures, combining nylon with chopped carbon fiber in order to improve key properties of the material. Onyx is 1.4 times stronger and stiffer than ABS and can be reinforced with any continuous fiber. The development of 3D printed continuous fibers has enabled a new category of stronger 3D printed parts.
With high strength and stiffness, excellent durability, and good chemical resistance, filled nylons such as Onyx are some of the few 3D printed thermoplastics tough enough for the factory floor. Nylon mixtures are suitable for fixtures, jigs, functional prototypes, and even end use parts.
PLA vs ABS vs Nylon: Making a Decision
PLA, ABS, and nylon are great beginner thermoplastics due to their low price point and general ease of printing. If you are looking to begin 3D printing for industrial use cases, however, filled nylons offer the superior material properties needed to withstand manufacturing environments.
To learn more about Markforged's continuous fibers, check out our blog post where we compare fiberglass with carbon fiber!