Torlon 4301 vs TP-PI
Polymer · grade comparison
Torlon 4301 and TP-PI are both polymer grades. Torlon 4301 is the stronger of the two: yield strength 108 MPa (15.7 ksi) against 90 MPa (13.1 ksi) for TP-PI, about 20% more; tensile strength follows at 117 MPa (17 ksi) vs 92 MPa (13.3 ksi). In exchange, TP-PI is the more ductile: elongation 40% versus 7% for Torlon 4301. TP-PI is lighter (1.33 g/cm³ vs 1.46 g/cm³ for Torlon 4301) and Torlon 4301 is stiffer (6.8 GPa vs 2.9 GPa). On the shop floor, TP-PI welds better (poor vs not recommended).
Torlon 4301Choose it when strength drives the design.
TP-PIChoose it when the part is bent, formed or impact-loaded, or when weight is the constraint.
Torlon 4301 vs TP-PI: 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
Poisson's Ratio
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Compressive Strength
Compressive Modulus
Flexural Strength
Flexural Modulus
Shear Strength
Izod Impact, Notched
Hardness, Rockwell M
Shear Modulus
Bulk Modulus
Hardness, Rockwell R
Same in both: Fracture Toughness (K_IC) 3 MPa·√m2.7 ksi·√in · Hardness, Shore D 88 Shore D
Physical
Density and transition temperatures.
Density
Glass Transition (Tg)
Water Absorption (24 h)
Water Absorption (Saturation)
Melting Temperature (Tm)
Refractive Index
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
Limiting Oxygen Index
Max Service Temperature (short-term)
Vicat Softening Point (B50)
Electrical
Conductivity and insulation.
Electrical Resistivity
Dielectric Strength
Dielectric Constant (1 MHz)
Dissipation Factor (1 MHz)
Volume Resistivity
Surface Resistivity
Comparative Tracking Index (CTI)
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Corrosion Resistance
UV / Weathering Resistance
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Weldability
Formability (cold)
Mold Shrinkage
Processing Melt Temperature (typ.)
Mold Temperature (typ.)
Melt Flow Rate
Same in both: Polishability 60 / 100
Sustainability
Primary-production footprint per kilogram.
Embodied Water
Same in both: Embodied Energy (primary production) 300 MJ/kg128,977 BTU/lb · Embodied Carbon (primary production) 15 kg CO₂/kg · Typical Recycled Content 0%
Common Calculations
Ratios derived from the values above.
Specific Strength (UTS / density)
Specific Stiffness (E / density)
Modulus of Resilience
Thermal Diffusivity
Same in both: 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 | Torlon 4301 | TP-PI |
|---|---|---|
| Default condition | — | — |
| Relative cost | $$$$ High | $$$$ High |
| Min. machined wall | — | — |
| Best machined surface | — | — |
Torlon 4301 vs TP-PI — frequently asked
Is Torlon 4301 stronger than TP-PI?
Yes. Torlon 4301 has a typical yield strength of 108 MPa (15.7 ksi) against 90 MPa (13.1 ksi) for TP-PI — about 20% more. Tensile strength is 117 MPa (17 ksi) vs 92 MPa (13.3 ksi).
Which is cheaper, Torlon 4301 or TP-PI?
Both sit in the same relative cost tier ($$$$, high); the part price will be decided by machining time, tolerance and quantity rather than by the material.
Which is easier to machine, Torlon 4301 or TP-PI?
TP-PI, by a small margin. Both rate good for machinability — 60/100 against 55/100 for Torlon 4301; for welding the order is TP-PI first (poor, 25/100) then Torlon 4301 (not recommended, 5/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in Torlon 4301 and TP-PI 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.