PLA · grade
PLA Tough
Properties of the Tough condition, compared with the other PLA grades.
Pick when parts must survive drops, screw bosses or snap fits — 3–5× the notched impact of plain PLA at slightly lower stiffness.
What is PLA Tough?
PLA Tough is PLA in the Tough grade — pick when parts must survive drops, screw bosses or snap fits — 3–5× the notched impact of plain PLA at slightly lower stiffness. PLA Tough has a yield strength of 45 MPa (6.53 ksi) and a tensile strength of 48 MPa (6.96 ksi) — weaker than 62% of polymer grades. Elongation at break is 15% and the elastic modulus is 2.9 GPa (0.421 Msi). PLA Tough has a density of 1.24 g/cm³ (0.0448 lb/in³), heavier than 63% of polymer grades. Its glass-transition temperature is 60°C (140 °F). Standard is the default condition FabDigit quotes; Tough is available on request or by drawing note.
Advantages
- Low embodied carbon — 1.8 kg CO₂/kg, better than 99% of polymer grades
- Low, predictable mold shrinkage — 0.4%, better than 82% of polymer grades
Limitations
- Needs corrosion protection — 55/100, worse than 96% of polymer grades
- Limited service temperature — 50°C (122 °F), worse than 94% of polymer grades
- Poor heat conductor — 0.13 W/m·K (0.0751 BTU/hr·ft·°F), worse than 82% of polymer grades
PLA Tough properties
Typical room-temperature values for PLA Tough — 11 properties are specific to this condition; the rest are grade-level values shared by every PLA grade. Each bar shows where the value sits among the polymer grades in FabDigit's library — further right is higher.
Physical7
PLA Tough has a density of 1.24 g/cm³ (0.0448 lb/in³), heavier than 63% of polymer grades. Its glass-transition temperature is 60°C (140 °F).
Mechanical16
PLA Tough has a yield strength of 45 MPa (6.53 ksi) and a tensile strength of 48 MPa (6.96 ksi) — weaker than 62% of polymer grades. Elongation at break is 15% and the elastic modulus is 2.9 GPa (0.421 Msi).
Thermal11
PLA Tough is rated for continuous service to 50°C (122 °F). It conducts heat at 0.13 W/m·K (0.0751 BTU/hr·ft·°F), worse than 82% of polymer grades. Thermal expansion is 70 µm/m·K (38.9 µin/in·°F).
Electrical6
PLA Tough is an electrical insulator with a dielectric strength of 19 kV/mm (482.6 V/mil) and a resistivity of 1×10¹⁴ Ω·m.
Chemical & Environmental3
Corrosion resistance is good (55/100), worse than 96% of polymer grades. UV resistance is fair.
Sustainability4
Producing a kilogram of PLA Tough takes about 50 MJ of energy and emits 1.8 kg of CO₂ — less than 99% of polymer grades. Typical recycled content is 2%.
Manufacturability8
PLA Tough's machinability is good (65/100, better than 66% of polymer grades); weldability very good (70/100); formability poor (25/100).
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Other PLA grades and fills
PLA is also supplied in 13 other conditions. The full side-by-side table is on the PLA overview.
- StandardDefaultDefault choice for visual prototypes, jigs and packaging where cost, print ease and dimensional accuracy matter more than toughness or heat resistance.50 MPa tensile
- GFCheaper stiffening route than CF with better strength retention; abrasive to brass nozzles and gives a rough, light-grey surface.62 MPa tensile
- IMPellet grades (e.g. Ingeo 2003D/3251D class) for moulded rigid packaging and cutlery — highest as-moulded strength but the same 55 °C HDT ceiling.58 MPa yield
- HTPLAChoose when the printed part must stay stiff above 60 °C: post-print annealing at 100–110 °C crystallises the resin and lifts HDT to ~90–120 °C (with ~1–2 % shrinkage).55 MPa tensile
- CFUse for stiff, matte-black, low-warp structural prints; nearly doubles modulus but is brittle and requires a hardened steel nozzle.52 MPa tensile
- ToughPick when parts must survive drops, screw bosses or snap fits — 3–5× the notched impact of plain PLA at slightly lower stiffness.45 MPa yield · 79 Shore D
- WoodDecorative composite that sands and stains like wood; mechanically weaker, clog-prone in small nozzles and needs low print temperatures to avoid charring.32 MPa tensile
- METALFor heavy, metallic-looking display parts that can be tumbled and polished to a real metal sheen; very abrasive and mechanically weak.25 MPa tensile
Working with PLA Tough
Is PLA easy to machine?
Machines easily with sharp single-flute cutters, high rpm and low feed, but heat build-up melts and re-welds chips — use air blast, avoid coolant with hot water, and expect brittle edge chipping when drilling.
Can PLA be welded?
Hot-plate, ultrasonic and friction welding all work below ~200 °C; solvent bonding with dichloromethane or ethyl acetate gives strong joints, and cyanoacrylate/epoxy adhere well after light sanding.
Can PLA be formed, bent or molded?
Prints at 190–220 °C nozzle / 50–60 °C bed with almost no warp and no enclosure needed; injection moulds at 185–215 °C into a 20–30 °C mould with 0.2–0.6 % shrinkage — dry pellets/filament to <250 ppm to prevent hydrolytic MW loss.
What surface finishes work on PLA?
Sand wet with 400–2000 grit, then polish or spray with acrylic/2K primer; acetone smoothing does not work (use ethyl-acetate wipe or UV/epoxy coat), and painting after a light key gives the most durable finish.
PLA chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| D-lactide unitshigher D content = more amorphous, lower Tm; 3DP grades ~4 % | 0.5 – 12 | 4 |
| residual lactide monomerISO/producer spec | 0 – 0.3 | 0.1 |
| nucleating agent / chain extendertalc, epoxy-functional oligomer in HT and IM grades | 0 – 3 | 0.5 |
| impact modifier (PBAT / acrylic core-she5–15 % in Tough / PLA+ variants | 0 – 15 | 0 |
| pigment / masterbatchcoloured filament | 0 – 4 | 2 |
| poly(L-lactide) (PLLA)backbone from fermented plant starch (corn/sugarcane) | ≥ 88 (balance) | — |
PLA Tough — frequently asked
What is PLA Tough used for?
PLA Tough is typically used for concept models, quick visual prototypes, form and fit-check parts, architectural and display models, low-temperature assembly jigs and master patterns for silicone moulds. In short: easy printable bioplastic.
What is the yield strength of PLA Tough?
PLA Tough has a typical yield strength of 45 MPa (6.53 ksi) and a tensile strength of 48 MPa (6.96 ksi) — weaker than 62% of polymer grades. Strength varies by condition: see the 14 listed tempers.
Is PLA Tough easy to machine?
Reasonably — machinability is rated good (65/100, better than 66% of polymer grades). Machines easily with sharp single-flute cutters, high rpm and low feed, but heat build-up melts and re-welds chips — use air blast, avoid coolant with hot water, and expect brittle edge chipping when drilling.
Can PLA Tough be welded?
Yes — weldability is rated very good (70/100). Hot-plate, ultrasonic and friction welding all work below ~200 °C; solvent bonding with dichloromethane or ethyl acetate gives strong joints, and cyanoacrylate/epoxy adhere well after light sanding.
What surface finishes work on PLA Tough?
Sand wet with 400–2000 grit, then polish or spray with acrylic/2K primer; acetone smoothing does not work (use ethyl-acetate wipe or UV/epoxy coat), and painting after a light key gives the most durable finish.
Can PLA Tough be formed, bent or molded?
Prints at 190–220 °C nozzle / 50–60 °C bed with almost no warp and no enclosure needed; injection moulds at 185–215 °C into a 20–30 °C mould with 0.2–0.6 % shrinkage — dry pellets/filament to <250 ppm to prevent hydrolytic MW loss.
What is the maximum service temperature of PLA Tough?
PLA Tough is rated for continuous use to about 50°C (122 °F), and briefly to 65°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between PLA Standard and PLA-IM?
Standard is the default condition — default choice for visual prototypes, jigs and packaging where cost, print ease and dimensional accuracy matter more than toughness or heat resistance. IM: pellet grades (e.g. Ingeo 2003D/3251D class) for moulded rigid packaging and cutlery — highest as-moulded strength but the same 55 °C HDT ceiling. Yield strength is 45 MPa in Standard versus 58 MPa in IM.
Can FabDigit make parts in PLA Tough?
Yes — PLA Tough is available for 3D printing with instant online pricing. Upload a STEP file to get a price and a DFM check.
Sources
- Ingeo Biopolymer 4043D / 3D850 / 2003D Technical Data Sheets — NatureWorks LLC (2023)
- Luminy PLA Grade Portfolio (L105, LX175, PLA+ blends) — TotalEnergies Corbion (2023)
- ISO 527-2 / ISO 178 / ISO 75-2 plastics test methods — ISO (2019)
- ASTM D638 / D256 / D648 / D792 — ASTM International (2022)
- CAMPUS Plastics — PLA datasets — CWFG / CAMPUS consortium (2024)
- Materials and the Environment / CES eco-property data for PLA — Ashby (Butterworth-Heinemann) (2021)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.