How does ABS compare to PLA in 3D printing?
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- Issue Time
- Dec 19,2024
The short answer
ABS is the tougher and far more heat resistant material: heat deflection of 95 to 100 °C against 50 to 57 °C for PLA, and 15 to 25 kJ/m2 notched impact against 3 to 5. PLA is stiffer, cheaper and prints without an enclosure. ABS needs a 95 to 110 °C bed, an enclosure and ventilation, and it warps on large parts.
Head to head: the numbers that decide it
Most ABS versus PLA arguments are really arguments about one property. On a desk at room temperature, PLA is the stiffer and easier material. In a warm, loaded or impact-prone environment, ABS is the answer. The six properties below settle the majority of real decisions.
| Property | PLA | ABS |
|---|---|---|
| Tensile strength | 45 to 60 MPa | 35 to 45 MPa |
| Stiffness, Young’s modulus | 3.3 to 3.5 GPa | 2.0 to 2.4 GPa |
| Elongation at break | 3 to 6 percent | 10 to 20 percent |
| Notched impact strength | 3 to 5 kJ/m2 | 15 to 25 kJ/m2 |
| Heat deflection at 0.45 MPa | 50 to 57 °C | 95 to 100 °C |
| Glass transition | 55 to 60 °C | 100 to 105 °C |
| Print temperature | 190 to 220 °C | 230 to 260 °C |
| Bed temperature | 50 to 60 °C, optional | 95 to 110 °C, required |
| Enclosure | Not required | Required for parts over about 50 mm |
| Warping | Negligible | High, about 0.8 percent shrink |
| Fumes | Low, faintly sweet | Styrene; ventilation is mandatory |
| UV and outdoor | Poor; fades and embrittles | Poor; yellows, use ASA instead |
| Post-processing | Sand and paint | Acetone smoothing, solvent welding |
| Price per kilogram | USD 15 to 25 | USD 18 to 30 |
Strength is not toughness
The most common selection mistake is reading the tensile row and stopping there. PLA wins that row, yet a PLA part is the one that cracks when it is dropped. The two properties measure different things: tensile strength is the stress a material carries before it breaks, and toughness is the energy it absorbs getting there.
The stress-strain curves show why. PLA rises almost linearly and then terminates at 3 to 6 percent strain with no yielding, so all the energy arrives in one brittle event. ABS yields at around 35 MPa and then draws: the specimen necks and extends to 10 to 20 percent strain while absorbing energy continuously. Notched impact testing separates the two even further, with ABS five to eight times tougher. A practical version of that test - a 3 mm printed enclosure dropped one metre onto concrete - cracks PLA most of the time and usually dents ABS.
Heat is where ABS separates
Nothing else about these two materials differs by as much as heat resistance. The heat deflection temperatures are roughly 40 to 45 °C apart, and that gap covers the entire range of everyday warm environments: a car interior in summer, a shelf near a window, a housing next to a power supply, a part above a motor.
Two details matter as much as the headline number. First, heat deflection is measured on an unloaded specimen at 0.45 MPa, so a loaded PLA part starts to move below the bottom of its band - a black PLA bracket on a dashboard sees 60 to 70 °C and sags within hours. Second, PLA creeps under load even at room temperature, so a shelf bracket can distort over months without ever getting hot. ABS behaves far better in both cases, which is why functional enclosures and anything near a heat source default to it.
Printing them: enclosure, ventilation and warping
Printable is not the same as easy. PLA prints on an open-frame machine with a 50 to 60 °C bed and tolerates imperfect settings. ABS needs a 95 to 110 °C bed and, for anything larger than a benchy, a chamber held around 40 to 50 °C so the part cools slowly and evenly. Without that, ABS shrinks about 0.8 percent as it cools, thermal stress builds, and corners lift or layers split. It also emits styrene during printing, so a ventilated or filtered enclosure is a working requirement rather than a preference.
The return on that effort is post-processing. ABS can be vapour smoothed with acetone into a glossy, sealed surface, solvent welded with the same liquid, and drilled, tapped and machined much like a conventional plastic. PLA can be sanded and painted, but it has no equivalent smoothing route, and sanding generates enough friction heat to soften it if you are heavy handed.
Which one wins for which job
| The part must | Choose | Why |
|---|---|---|
| Be cheap and fast to iterate | PLA | Lowest material cost, no enclosure, fewest failed prints |
| Hold a static load indoors | PLA, or PETG if loaded long term | Highest stiffness at room temperature, but PLA creeps |
| Survive being dropped | ABS | Five times the notched impact energy of PLA |
| Sit near heat, up to about 95 °C | ABS or ASA | Heat deflection 95 to 100 °C against 50 to 57 °C |
| Live outdoors | ASA, not ABS | ABS yellows and embrittles in UV; ASA is stabilised |
| Look glossy without painting | ABS | Acetone vapour smoothing; no PLA equivalent |
| Be a smooth-looking concept model | PLA | Sharpest detail and the widest finish range |
Where each one fails
- PLA in a hot car. Softening starts around 55 to 60 °C, so a dashboard part distorts under its own weight in a single summer afternoon.
- PLA under a steady load. Creep at room temperature means a bracket or a phone mount slowly changes shape while looking fine for weeks.
- ABS on an open printer. Differential cooling warps the part and splits layers, so the printed strength lands below the datasheet even when the spool is good.
- ABS outdoors. UV yellowing and embrittlement arrive within a season or two; ASA exists precisely for that duty.
- ABS without ventilation. Styrene exposure is a health issue, not a smell complaint, and it is the reason many workshops run ABS behind a filter.
Consider PETG before either one. PETG sits between them at 70 to 80 °C heat deflection with 8 to 12 kJ/m2 impact, prints without an enclosure and costs about the same as ABS. Where the requirement is "tougher than PLA but not 100 °C", PETG usually answers it with less printer hardware and less warping risk.
Choosing between ABS and PLA at SOMI Custom Parts
We print both, and the recommendation comes from the service environment rather than the price list. Send the model with the temperature, load and UV exposure the part will actually see and we will tell you where PLA is enough, where PETG covers it more cheaply than ABS, and where an engineered polymer or nylon is the honest answer: see FDM 3D printing, SLS 3D printing or SLA 3D printing.
Scope and sources. Mechanical and thermal values are typical published ranges for commercial filament in 2026, cross-checked against a mechanical comparison of PLA, PETG and ABS with tensile and notched impact data, a PLA versus ABS printing guide and a cost and performance review of FDM materials. Printed properties are orientation dependent and fall between layers, so treat the figures as planning ranges. Where a part carries a structural, thermal or regulatory requirement, verify it on printed coupons in the final orientation.