PLA is the most popular 3D printing filament in the world. It’s cheap, easy to print and comes in every colour imaginable. But is it strong enough for parts that actually get used? Here’s the honest answer.
How strong is PLA?
Stronger than many people think, but brittle.
- Tensile strength: standard PLA is surprisingly strong when you pull on it, often comparable with or better than PETG and ABS.
- Stiffness: PLA is stiff, so it holds its shape well under light loads.
- Toughness: this is PLA’s weak spot. It doesn’t bend much before it snaps, so drops and impacts can crack it.
- Heat: PLA starts to soften at around 55–60°C. A PLA part left in a hot car or next to a motor can warp.
- Layer adhesion: like all FDM prints, PLA parts are weakest between layers.
In short: PLA is strong and stiff, but it isn’t tough, and it doesn’t like heat.
PLA vs PETG: which is stronger?
| PLA | PETG | |
|---|---|---|
| Tensile strength | Similar or higher | Similar |
| Stiffness | Higher | Lower (more flexible) |
| Impact toughness | Lower (brittle) | Higher (bends before breaking) |
| Heat resistance | ~55–60°C | ~75–80°C |
| Ease of printing | Easiest | Easy (can be stringy) |
Choose PETG when a part needs to flex, take knocks or sit somewhere warm.
Choose PLA when you need stiffness, fine detail and the easiest printing.
What is “tough PLA”?
Tough PLA (also sold as PLA+ or “pro” PLA) is PLA with additives that make it less brittle, so it absorbs more energy before it cracks. The trade-off is often slightly lower stiffness.
Graphene SuperTough PLA: stronger and tougher
Graphene-enhanced PLA takes a different approach. Instead of softening the PLA to make it tougher, well-dispersed graphene reinforces it. You get gains in strength, stiffness and layer toughness together.
Our Graphene SuperTough PLA gives you, compared with standard PLA:
- 25% higher tensile strength
- 35% higher stiffness
- 45% higher strain to failure in the Z-direction: layers hold together better, so parts are less likely to split along a layer line
- 3x thermal conductivity, which spreads heat more evenly
It prints on exactly the same settings as normal PLA: no hardened nozzle, no enclosure. Read Why Is Graphene So Strong? for the science.
Note: graphene PLA is still PLA, so it shares PLA’s softening point. For parts that must survive high temperatures, see our heat resistant filament guide.
When should you upgrade from standard PLA?
Upgrade if your PLA parts:
- crack when dropped or clipped together
- split along layer lines under load
- need to look and behave like a finished product, for example in prototypes, brackets, mounts, jigs and robotics parts
Shop strong PLA in the UK
SuperTough PLA 1.75mm · SuperTough PLA 2.85mm
UK stock, dispatched within 24 working hours. See also: Strongest 3D Printing Filament: UK Guide.
FAQ
Is PLA stronger than ABS?
In tensile strength, PLA is often stronger. ABS is tougher and much more heat resistant.
Can PLA be used for functional parts?
Yes, for many indoor, low-temperature parts. For heavier loads or impact, use a tougher or graphene-enhanced PLA.
Does infill make PLA stronger?
Yes, but adding more walls (perimeters) usually increases strength more than adding infill.