For this article, we compare the three different nylon based materials offered by Stratasys for FDM 3D printing. Each of these materials have their own advantages and drawbacks. Keep reading to learn about the technical properties of Nylon 6, Nylon 12 and Nylon 12CF (carbon filled) and why you would choose one material over another for your next engineering project.
What is Nylon?
Originally developed by DuPont, nylon was the first commercially successful synthetic thermoplastic polymer. It was first used in nylon bristled toothbrushes and women’s stockings, or “nylons”, in the late 1930s. Nylon polymers have many applications and can be mixed with a variety of additives to achieve different properties. Because of its incredible elasticity and strength, nylon found significant success in commercial applications in a wide range of industries.
FDM Nylon Materials Offered by Stratasys
Nylon 6
Stratasys boasts that Nylon 6 “offers the best combination of strength and toughness of any FDM material”. This material is great for parts that require good tensile and mechanical strength, while being able to withstand rigorous functional testing. Currently, Nylon 6 is only available in black on the Fortus 900mc and uses an SR-110 soluble support material.
Nylon 12
Nylon 12 is “the toughest in the industry” exhibiting 100-300% better elongation at break and superior fatigue resistance over any other additive manufacturing technology. Nylon 12 is great for applications that demand high endurance, strength and flexibility. Snap fits and friction inserts are ideal applications for Nylon 12. It is also compatible with the Fortus 900mc as well as the Fortus 450mc and the Fortus 380mc. Similar to Nylon 6, Nylon 12 is available in black and uses SR-110 soluble support material.
Nylon 12 CF
Carbon-fiber reinforced Nylon 12 thermoplastic was developed to meet the needs of the production environment as an alternative to metal tooling. Nylon 12CF has the highest flexural strength of any FDM thermoplastic. Made up of a blend of Nylon 12 and 35% chopped carbon fiber, it’s ideal applications are for strong but lightweight tooling applications and functional prototypes. Nylon 12CF is available on the Fortus 450mc with an upgraded print head developed specifically for Nylon 12CF. Nylon 12CF is available in black and compatible with SR-110 support material.
Strength and Flexibility Comparison:
To compare the different nylon materials offered by Stratasys by strength and flexibility, we devised a simple experiment. Using tensile bars of the same size in each material, we mounted the bars to a fixed point in our workshop. At that point. we then hung a weight (500 grams plus 9.66 grams for carabiner equals 509.66 grams of weight) from the opposite end. Next, we used a Space Spider Artec 3D scanner to help record the resulting bend of the different materials relative to a control bar. Below are examples of our procedure for this experiment and the resulting data we received from scanning the parts.
Here, we are 3D scanning a nylon tensile bar with weighted load to record the physical bending of the material. We used a control bar to act as a reference point and measured the bending distance from the beginning, midpoint and furthest point away from the axis.
Above: Nylon 6 – Bent 35.25mm from the control at the farthest point (point 3)
Above: Nylon 12 – Bent 40.38mm from the control at the farthest point (point 3)
Above: Nylon 12CF – Bent 17.27mm from the control at the farthest point (point 3)
Above: Combined image of the three experiments showing the strength comparison between the three Nylon materials being tested
Final Results:
This graph illustrates the deformation distance, or deviation from the control bar of the different nylon materials tested. We also found the average deviation of the three reference points for each material.
|
Point 1 | Point 2 | Point 3 | Average Change (mm) | |
Nylon 6 | 4.09 | 14.08 | 35.25 | 17.8
20.3
8.6
|
|
Nylon 12 | 3.85 | 16.63 | 40.38 | ||
Nylon 12CF | 2.28 | 6.34 | 17.27 |
Some important observations were made from analyzing this data. Most notably, was that Nylon 12CF is over twice as strong as the other nylons. This experiment also showed that Nylon 6 is slightly more ridged than Nylon 12, making Nylon 12 the most flexible of the nylons. While this experiment does not accurately test tensile strength to the point of breakage, it is a good indicator of what types of loads the materials can handle. Nylon is an excellent choice of material when high strength and some flexibility is required. Nylon 12CF is incredibly strong and is a great option for engineers looking for a low weight and high strength, while still being an affordable alternative to tooling with metal.
Learn more about Nylon 12 best practices by downloading our whitepaper.