3D printing plastic strength


Are 3D Printed Parts Strong & Durable? PLA, ABS & PETG – 3D Printerly

Companies worldwide have recently turned to 3D printing to create technical parts quickly while saving some money in the process. But, developing 3D versions of pieces involves using new materials that might not be as durable. So, are 3D printed parts strong?

3D printed parts are very strong, especially when using specialized filament like PEEK or Polycarbonate, which is used for bullet-proof glass and riot shields. Infill density, wall thickness and print orientation can be adjusted to increase strength.

There’s a lot that goes into the strength of a 3D part. So, we’re going to be reviewing the materials used during 3D printing, how strong they really are, and what you can do to increase the strength of your 3D printed parts.

Are 3D Printed Parts Weaker & Fragile?

No, 3D printed parts aren’t weaker and fragile unless you 3D print them with settings that don’t give strength. Creating a 3D print with a low level of infill, with a weaker material, with a thin wall thickness and low printing temperature is likely to lead to a 3D print that’s weak and fragile.

How Do You Make 3D Printed Parts Stronger?

Most 3D printing materials are rather durable on their own, but there are some things that can be done to increase their overall strength. This mostly comes down to the minor details in the design process.

Most important would have to be manipulating the infill, wall thickness, and the number of walls. So, let’s take a look at how each of these factors can impact the strength of a 3D printed structure.

Increase Infill Density

Infill is what’s used to fill in the walls of a 3D printed part. This is essentially the pattern within the wall that adds to the density of the piece overall. Without any infill, the walls of a 3D part would be completely hollow and rather weak to outside forces.

Infill is a great way to increase the weight of a 3D part, also improving the strength of the part at the same time.

There are plenty of different infill patterns that can be used to improve the strength of a 3D printed piece, including a grid infill or a honeycomb infill. But, just how much infill there is will determine the strength.

For regular 3D parts, up to 25% is likely more than enough. For pieces designed to support weight and impact, closer to 100% is always better.

Increase Number of Walls

Think of the walls of a 3D printed part as the support beams in a house. If a house only has four exterior walls and no support beams or interior walls, just about anything can cause the house to collapse or give under any amount of weight.

In the same way, the strength of a 3D printed piece will only exist where there are walls to support weight and impact. That’s exactly why increasing the number of walls inside a 3D printed piece can increase the strength of the structure.

This is an especially useful strategy when it comes to larger 3D printed parts with a greater surface area.

Increase Wall Thickness

The actual thickness of the walls used in a 3D printed piece will determine how much impact and weight a part can withstand. For the most part, thicker walls will mean a more durable and sturdy piece overall.

But, there does seem to be a point at which it’s difficult to print 3D printed parts when the walls are too thick.

The best part about adjusting the wall thickness is that the thickness can vary based on the area of the part. That means the outside world probably won’t know that you’ve thickened the walls unless they cut your piece in half to dissect it.

Generally speaking, extremely thin walls will be quite flimsy and won’t be able to support any exterior weight without collapsing.

Generally, walls that are at least 1.2mm thick are durable and strong for most materials, but I’d recommend going up to 2mm+ for a higher level of strength.

The Strength of Materials Used to Create 3D Parts

3D printed parts can only be as strong as the material that they’re made of. With that said, some materials are a lot stronger and more durable than others. That’s exactly why the strength of 3D printed parts varies so greatly.

Three of the more common materials used to create 3D parts include PLA, ABS, and PETG. So, let’s discuss what each of these materials is, how they can be used, and how strong they really are.

PLA (Polylactic Acid)

PLA, also known as Polylactic Acid, is perhaps the most popular material used in 3D printing. Not only is it quite cost-effective, but it’s also very easy to use to print parts.

That’s why it’s often used to print plastic containers, medical implants, and packaging materials. In most circumstances, PLA is the strongest material used in 3D printing.

Even though PLA has an impressive tensile strength of about 7,250 psi, the material does tend to be a little brittle in special circumstances. That means it’s a little more likely to break or shatter when placed under a powerful impact.

It’s also important to note that PLA has a relatively low melting point. When exposed to high temperatures, the durability and strength of PLA will severely weaken.

ABS (Acrylonitrile Butadiene Styrene)

ABS, also known as Acrylonitrile Butadiene Styrene, isn’t quite as strong as PLA, but that doesn’t at all mean that it’s a weak 3D printing material. In fact, this material is much more capable of withstanding heavy impact, often flexing and bending rather than shattering completely.

That’s all thanks to the tensile strength of about 4,700 PSI. Given the lightweight construction yet impressive durability, ABS is one of the best 3D printing materials out there.

That’s why ABS is used to make just about any type of product in the world. It’s quite a popular material when it comes to printing children’s toys like Legos, computer parts, and even piping segments.

The incredibly high melting point of ABS also makes it able to withstand just about any amount of heat.

PETG (Polyethylene Terephthalate Glycol-Modified)

PETG, also known as Polyethylene Terephthalate, is usually used to develop more complex designs and objects when it comes to 3D printing. That’s because PETG tends to be much denser, more durable, and more rigid than some of the other 3D printing materials.

For that exact reason, PETG is used to make plenty of products like food containers and signage.

Why Use 3D Printing at All?

If 3D printed parts weren’t at all strong, then they wouldn’t be used as an alternative production method for many supplies and materials.

But, are they as strong as metals like steel and aluminum? Definitely not!

However, they are quite useful when it comes to designing new pieces, printing them at a lower cost, and getting a good amount of durable use out of them. They’re also great for small parts and have a generally decent tensile strength given their size and thickness.

What’s even better is that these 3D printed parts can be manipulated to increase their strength and overall durability.

Conclusion

3D printed parts are definitely strong enough to be used to make common plastic items that can withstand great amounts of impact and even heat. For the most part, ABS tends to be much more durable, though it does have a much lower tensile strength than PLA.

But, you also need to take into consideration what’s being done to make these printed parts even stronger. When you bump up the infill density, increase the number of walls, and improve the wall thickness, you’re adding to the strength and durability of a 3D printed piece.

What is the Strongest 3D Printer Filament?

What is the strongest 3D printer filament? Airwolf 3D CEO and Co-Founder Erick Wolf gives a rundown on the results of a 3D printer filament strength test featuring PLA, ABS, Nylon, and Polycarbonate. This blog post was adapted from the video, What is the Strongest 3D Printer Filament? and is part of the series, Hooked on 3D Printing: A Study in Material Strength.

Hi everybody, Erick Wolf here from Airwolf 3D. Today I’m going to talk about the strength of commonly — and not so commonly — 3D-printed materials. Specifically, we’ll be testing PLA, ABS, NYLON 910, and POLYCARBONATE.

We’ll test each material by printing a common hook and then loading the hook with weight until it fractures. The hook that takes the most weight will correspond to the material with the greatest tensile strength. To back it up, we’ll pull some information from a great article on 3DPrint.com referring to tensile strength of commonly 3D-printed materials.

To keep it interesting, we set up a fun experiment using our 3D-printed hooks to pick up a tractor tire weighing 150 pounds and loaded with hundreds of pounds of additional weights from Precision Fitness, our local gym here in Costa Mesa, CA.

To test the strength of hooks printed in different 3D-printing materials, the Wolfpack loaded up a tractor tire with weights from a local gym and 50-lb bags of raw polycarbonate plastic pellets that the company uses for manufacturing filament.

So let’s get on with it and start talking about our materials. The most popular desktop filament is probably polylactic acid, or PLA. We print PLA with the heated bed at 60 degrees Celsius and a coat of Wofbite Nano. It’s also best to keep the lid off as PLA is sensitive to high temperatures. PLA is an environmentally friendly, compostable filament that prints easily at low temperatures and looks great. It’s also pretty strong.

It’s pretty darn impressive that PLA survived up to a 285 lb lift. We probably could have eked a few more pounds out of it, but the hook was already yielding. Truth be told, we were surprised with PLA’s strength. However, with a tensile strength of 7,250 psi, this is a strong material. With that comes a caveat, In this case, a caveat that can swallow the entire utility of PLA. Because PLA is biodegradable, don’t be surprised if it starts breaking down during use. In the sun especially, PLA is unpredictable and can change forms with a few hours. So please don’t print your tow hook out of PLA — it should not be used for anything supporting a load. Stick to what PLA is best for, toys and figurines.

Material Showdown: ABS vs PLA

Next up, let’s look at a real engineering material, ABS. ABS is used just about everywhere, including your car, home, and office for everything from interior bits and pieces to your mouse and computer case. Airwolf 3D was one of the first companies to make desktop 3D printers capable of printing in ABS. Why? Because ABS is an engineering-grade material that can be sanded, finished, painted, and used in real world applications for end-use components. In fact, we printed out thousands of 3D printers using ABS as the main material. For best printing, keep your heated bed to at least 120 degrees Celsius, apply a coat of Wolfbite and print in an enclosed environment. We optimized the AXIOM 3D printer for ABS and hotter materials.

Now for the real test. How did ABS compare to PLA? As ABS and PLA are the most frequently used materials on the desktop, which one is stronger? Turns out ABS is weaker than PLA. With the same 285 lb load, the ABS hook snapped instantly.

We didn’t bother to reduce the weight as this is really meant to be a test of ultimate strength. The results should not come as a surprise, however, because ABS has a lower tensile strength of 4,700 psi compared with 7,250 psi from PLA. However, you could design a stronger hook using more material out of ABS that could match our PLA hook’s strength. In that case, you would not have to worry about the unpredictable nature of PLA.

But we’re really here to find the strongest 3D printing material for your desktop printer. And for that, we need to start looking into more exotic materials, starting with nylon.

Testing the Strength of Nylon

There is a great type of nylon for 3D printing called Nylon 910. We print Nylon 910 at 250 degrees Celsius with the bed at 70-100 degrees Celsius, using Wolfbite Nitro for the ultimate bed adhesion. Also remember to print in an enclosed environment for best results.

Nylon is a great material for making structural parts. Compared to ABS with a tensile strength of 4,700 psi, nylon’s estimated tensile strength of 7,000 psi is head and shoulders above ABS. Notice how I stated “estimated.” I say that because there are several different types of nylon with strength varying in between.

In the video, notice how the hook initially bent, but didn’t yield until hundreds of pounds later, 485 pounds in this case. As we can see, nylon is a predictable material that works great in load applications. In fact, every Airwolf 3D printer built over the course of the last three years uses 3D-printed nylon gears for the ultimate in performance and wear characteristics.

Polycarbonate: The True King of Desktop 3D Printer Filaments?

Now let’s talk about polycarbonate. Since 2014 with the introduction of the Airwolf HDx, we’ve been printing in this incredibly strong and heat-resistant material. What makes printing polycarbonate unique is the extraordinarily high temperatures. First, the bed should be at 145 degrees Celsius or higher. Second, the head should be at 290 degrees Celsius or higher. Both of those temps are far, far out of the range of conventional desktop 3D printers. Finally, you’ll need to enclose polycarbonate as it will warp quickly if printed in an open environment.

The collection of broken 3D-printed hooks after completing the material strength test.

So how did polycarbonate fare? We suspended 685 pounds from that little hook! Polycarbonate is the undisputed king of materials for desktop 3D printing. Even we were surprised at polycarbonate’s strength. In comparison to nylon at 7,000 psi, polycarbonate’s tensile strength of 9,800 psi makes it the ideal choice for high-strength, functional components. When printed correctly, such as on an Axiom 3D printer, PC is an incredibly strong material. Also, remember that PC has a much higher glass transition temperature than all the other plastics mentioned here. Compared to its closest competitor, ABS, polycarbonate can take about 40 degrees more heat before deforming. In short, polycarbonate is the undisputed king of desktop 3D materials.

Tensile Strength ISO 527

In addition to this fun “hook test”, Airwolf 3D staff tested its engineering-grade materials using consistent, repeatable ISO 527 standards. You can read more about this here: Material Testing Part 1: Tensile Strength ISO 527 and you can also download data sheet for each material by following the hyperlink below.

910 ALLOY
MG94 ABS FILAMENT
PETG FILAMENT
PREMIUM PLA FILAMENT
POLYPROPYLENE FILAMENT
WOLFBEND TPU FLEXIBLE FILAMENT
BRIDGE NYLON FILAMENT
Specifications
TENSILE STRENGTH 47.7 MPa 46.4 Mpa 50.0 MPa 64.4 Mpa 12.8 MPa 23.8 MPa 40.2 MPa
ELONGATION AT BREAK 28.8% 21. 6% 21.5% 15.3% 716.0% 909.0% 401.0%
EXTRUDER TEMPERATURE 240C – 250C 235C – 260C 235C – 255C 195C – 225C 210C – 220C 230C – 245C 255C – 270C
BED TEMPERATURE 70C – 80C 110C – 130C 80C – 120C 60C – 70C 80C – 100C 40C – 60C 80C – 100C
HEATED BED Required Required Required Optional Required Optional Required
RECOMMENDED BUILD SURFACE Wolfbite NITRO Wolfbite for ABS, PETG, TPU, and TPE Wolfbite for ABS, PETG, TPU, and TPE WolfBite Nano Wolfbite ULTRA Wolfbite for ABS, PETG, TPU, and TPE Wolfbite NITRO
DIAMETER 2.88mm 2.88mm 2.88mm 2.88mm 2.88mm 2.88mm 2. 88mm
COLOR Black, Natural Black, Black 5lbs, Natural, Natural 5lbs, White, White 5lbs Black, Blue, Red, White, Yellow Black, Blue, Green, Natural, Orange, Red, Silver, White, Yellow White Black, Blue, Clear, Red, White Black, Natural
COMPATIBLE MACHINE AXIOM, AXIOM 20, AXIOM Dual Extruder, EVO AXIOM, AXIOM 20, AXIOM Dual Extruder, EVO AXIOM, AXIOM 20, AXIOM Dual Extruder, EVO AXIOM, AXIOM 20, AXIOM Dual Extruder, AXIOMe, EVO AXIOM, AXIOM 20, AXIOM Dual Extruder, EVO AXIOM, AXIOM 20, AXIOM Dual Extruder, AXIOMe, EVO AXIOM, AXIOM 20, AXIOM Dual Extruder, EVO
910 ALLOY MG94 ABS FILAMENT PETG FILAMENT PREMIUM PLA FILAMENT POLYPROPYLENE FILAMENT WOLFBEND TPU FLEXIBLE FILAMENT BRIDGE NYLON FILAMENT

Download Material List

Did you know that you can 3d print in over 40+ materials?

There are dozens of types of filaments available to you, including harder polymers such as polycarbonate and flexible materials such as TPU. Download this handy list of commonly used materials. This two page reference chart includes the recommended hotend temperature and bed temperature for optimal 3D printing settings of each material.

What is the most durable material for 3D printing?

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