PHB vs PLLA
Polymer · grade comparison
PHB and PLLA are both polymer grades. PLLA is the stronger of the two: yield strength 60 MPa (8.7 ksi) against 35 MPa (5.08 ksi) for PHB, about 71% more; tensile strength follows at 62 MPa (8.99 ksi) vs 36 MPa (5.22 ksi). In exchange, PHB is the more ductile: elongation 5% versus 4% for PLLA, and PLLA is harder (83 Shore D vs 78 Shore D). PHB runs hotter in service (100°C vs 55°C continuous) and PHB conducts heat better (0.2 W/m·K vs 0.16 W/m·K). On the shop floor, PLLA welds better (very good vs fair).
PHBChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.
PLLAChoose it when strength drives the design, or when it will be welded.
PHB vs PLLA: propertiesHow to read these bars
- One bar per material. A full bar is the highest value among all polymer grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
How to read these bars
- One bar per material. A full bar is the highest value among all polymer grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
Mechanical
Strength, stiffness, ductility and hardness at room temperature.
Poisson's Ratio
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Compressive Strength
Flexural Strength
Flexural Modulus
Izod Impact, Notched
Hardness, Shore D
Hardness, Rockwell R
Shear Modulus
Bulk Modulus
Compressive Modulus
Fracture Toughness (K_IC)
Same in both: Elastic (Young's) Modulus 3.5 GPa0.51 Msi
Physical
Density and transition temperatures.
Density
Glass Transition (Tg)
Light Transmission
Same in both: Melting Temperature (Tm) 175°C347 °F · Water Absorption (24 h) 0.4% · Water Absorption (Saturation) 1% · Refractive Index 1.46
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Thermal Expansion (CTE, 20–100 °C)
Max Service Temperature (continuous)
Min Service Temperature
Heat Deflection Temp. @ 0.45 MPa
Heat Deflection Temp. @ 1.8 MPa
Vicat Softening Point (B50)
Limiting Oxygen Index
Max Service Temperature (short-term)
Same in both: Specific Heat Capacity 1,500 J/kg·K0.36 BTU/lb·°F
Electrical
Conductivity and insulation.
Electrical Resistivity
Dielectric Strength
Volume Resistivity
Dissipation Factor (1 MHz)
Surface Resistivity
Same in both: Dielectric Constant (1 MHz) 3
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
UV / Weathering Resistance
Corrosion Resistance
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Weldability
Formability (cold)
Polishability
Mold Shrinkage
Melt Flow Rate
Processing Melt Temperature (typ.)
Mold Temperature (typ.)
Sustainability
Primary-production footprint per kilogram.
Embodied Energy (primary production)
Embodied Carbon (primary production)
Same in both: Typical Recycled Content 0%
Common Calculations
Ratios derived from the values above.
Specific Strength (UTS / density)
Modulus of Resilience
Same in both: Specific Stiffness (E / density) 2.8 MN·m/kg · Thermal Diffusivity 0.1 mm²/s · Thermal Shock Resistance Index 0
Strength versus weight
Yield strength against density for every polymer grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.
Manufacturing and finishing
| Capability | PHB | PLLA |
|---|---|---|
| Default condition | — | — |
| Relative cost | $$$ Premium | $$$ Premium |
| Min. machined wall | — | — |
| Best machined surface | — | — |
PHB vs PLLA — frequently asked
Is PLLA stronger than PHB?
Yes. PLLA has a typical yield strength of 60 MPa (8.7 ksi) against 35 MPa (5.08 ksi) for PHB — about 71% more. Tensile strength is 62 MPa (8.99 ksi) vs 36 MPa (5.22 ksi).
Which is cheaper, PHB or PLLA?
Both sit in the same relative cost tier ($$$, premium); the part price will be decided by machining time, tolerance and quantity rather than by the material.
Which is easier to machine, PHB or PLLA?
PLLA, by a small margin. Both rate good for machinability — 60/100 against 55/100 for PHB; for welding the order is PLLA first (very good, 75/100) then PHB (fair, 50/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in PHB and PLLA side by side — material, machining time, tolerance and finish in one quote. Certified material data ships with the order on request.
Typical handbook values for the conditions named above, normalised for comparison. Hardness on non-Brinell scales is converted approximately for charting only. Request certified data with your order for design-critical properties.