PDLA vs PHB
Polymer · grade comparison
PDLA and PHB are both polymer grades. PDLA is the stronger of the two: yield strength 58 MPa (8.41 ksi) against 35 MPa (5.08 ksi) for PHB, about 66% more; tensile strength follows at 60 MPa (8.7 ksi) vs 36 MPa (5.22 ksi). In exchange, PHB is the more ductile: elongation 5% versus 4% for PDLA, and PDLA is harder (83 Shore D vs 78 Shore D). PHB is stiffer (3.5 GPa vs 3.3 GPa) and PHB runs hotter in service (100°C vs 50°C continuous). On the shop floor, PDLA welds better (good vs fair) and PHB sits in a lower cost tier (premium, $$$) than PDLA (high, $$$$).
PDLAChoose it when strength drives the design, or when it will be welded.
PHBChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.
PDLA vs PHB: 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.
Elastic (Young's) Modulus
Shear Modulus
Bulk Modulus
Poisson's Ratio
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Compressive Strength
Compressive Modulus
Flexural Strength
Flexural Modulus
Shear Strength
Fracture Toughness (K_IC)
Izod Impact, Notched
Hardness, Shore D
Same in both: Hardness, Rockwell R 105 HRR
Physical
Density and transition temperatures.
Melting Temperature (Tm)
Glass Transition (Tg)
Refractive Index
Light Transmission
Same in both: Density 1.25 g/cm³0.05 lb/in³ · Water Absorption (24 h) 0.4% · Water Absorption (Saturation) 1%
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Specific Heat Capacity
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)
Electrical
Conductivity and insulation.
Electrical Resistivity
Dissipation Factor (1 MHz)
Volume Resistivity
Surface Resistivity
Comparative Tracking Index (CTI)
Same in both: Dielectric Strength 20 kV/mm508 V/mil · Dielectric Constant (1 MHz) 3
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Corrosion Resistance
Same in both: UV / Weathering Resistance 35 / 100
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)
Embodied Water
Same in both: Typical Recycled Content 0%
Common Calculations
Ratios derived from the values above.
Specific Strength (UTS / density)
Specific Stiffness (E / density)
Modulus of Resilience
Same in both: 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 | PDLA | PHB |
|---|---|---|
| Default condition | — | — |
| Relative cost | $$$$ High | $$$ Premium |
| Min. machined wall | — | — |
| Best machined surface | — | — |
PDLA vs PHB — frequently asked
Is PDLA stronger than PHB?
Yes. PDLA has a typical yield strength of 58 MPa (8.41 ksi) against 35 MPa (5.08 ksi) for PHB — about 66% more. Tensile strength is 60 MPa (8.7 ksi) vs 36 MPa (5.22 ksi).
Which is cheaper, PDLA or PHB?
PHB is the lower-cost material: it sits in the premium tier ($$$) while PDLA is high ($$$$). Part price depends far more on geometry, tolerance and quantity than on raw stock — upload a CAD file for a live quote.
Which is easier to machine, PDLA or PHB?
PDLA, by a small margin. Both rate good for machinability — 60/100 against 55/100 for PHB; for welding the order is PDLA first (good, 60/100) then PHB (fair, 50/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in PDLA and PHB 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.