Torlon 4301
Torlon 4301 is a filled, wear-resistant polyamide-imide (PAI) that uses graphite content to add stiffness, creep resistance and dimensional stability compared with unfilled 4203.
Reference datasheet — Torlon 4301 is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the PC condition
Torlon 4301 grades and fills
Torlon 4301 is supplied in 7 conditions, soft to hard. PC is the default FabDigit quotes; the values on this page are for it.
Compare all 7 grades and fillsHide
| Grade · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness |
|---|---|---|---|---|---|
Torlon 4630 | Maximum-lubricity PAI compound for dry-running and high-speed seal/bearing surfaces where the lowest wear rate outweighs strength. | 90 | 95 | 5 | 88 Shore D |
4301 as-molded / uncured | Condition straight out of the mold before the multi-day 260 °C cure — only for parts that will be cured after machining; mechanical, wear and solvent performance are well below cured values. | 92 | 100 | 11 | 86 Shore D |
PCDefault 4301 post-cured | Standard delivered condition — pick for all load-bearing wear parts (rings, bushings, thrust washers) needing full strength, creep and chemical resistance at 200–250 °C. | 108 | 117 | 7 | 88 Shore D |
Torlon 4275 | Higher graphite loading than 4301 — pick for higher PV bearing/seal duty and better thermal conduction, accepting lower strength and toughness. | 113 | 6 | ||
Torlon 4203L | Sibling unfilled grade — pick when maximum toughness, elongation and electrical insulation matter more than wear resistance or stiffness. | 192 | 15 | ||
Torlon 7130 | Highest stiffness and lowest CTE PAI grade with some static dissipation — pick for metal-replacement structural and precision parts under high temperature. | 203 | 6 | ||
Torlon 5030 | The true glass-reinforced PAI grade — pick for stiff, dimensionally stable structural aerospace/oilfield parts where electrical insulation is also required. | 205 | 7 |
Supply forms, finishes and certifications
Ways Torlon 4301 is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
STOCK | 4301 machining stock | Surface finish |
What is Torlon 4301?
Torlon 4301 is a filled, wear-resistant polyamide-imide (PAI) that uses graphite content to add stiffness, creep resistance and dimensional stability compared with unfilled 4203. Tensile strength is 117 MPa with 7% elongation and continuous service to 250 °C, which suits structural aerospace brackets and downhole hardware under combined temperature and pressure. It is available as-moulded, post-cured and as stock shapes; parts require a multi-day post-cure, cannot be melt-welded and machine abrasively. Choose 4203 for higher elongation, or 7130 when carbon-fibre stiffness is needed. Torlon 4301 has a density of 1.46 g/cm³ (0.0527 lb/in³), heavier than 86% of polymer grades. Its glass-transition temperature is 275°C (527 °F). Torlon 4301 has a yield strength of 108 MPa (15.7 ksi) and a tensile strength of 117 MPa (17 ksi) — stronger than 98% of polymer grades. Elongation at break is 7% and the elastic modulus is 6.8 GPa (0.986 Msi).
What is Torlon 4301 used for?
- aerospace structural brackets
- downhole tool components
- high-load bushings
Advantages
- Conducts heat well — 0.54 W/m·K (0.312 BTU/hr·ft·°F), better than 99% of polymer grades
- High strength — 108 MPa (15.7 ksi), better than 98% of polymer grades
- High service temperature — 250°C (482 °F), better than 94% of polymer grades
- Stiff — 6.8 GPa (0.986 Msi), better than 90% of polymer grades
- Low, predictable mold shrinkage — 0.3%, better than 90% of polymer grades
Limitations
- High embodied carbon — 15 kg CO₂/kg, worse than 96% of polymer grades
- Limited formability — 5/100, worse than 95% of polymer grades
- Difficult to weld — 5/100, worse than 89% of polymer grades
- Heavy — 1.46 g/cm³ (0.0527 lb/in³), worse than 86% of polymer grades
Torlon 4301 properties
Typical room-temperature values for Torlon 4301-PC; bars are the position among polymer grades.
Physical4
Torlon 4301 has a density of 1.46 g/cm³ (0.0527 lb/in³), heavier than 86% of polymer grades. Its glass-transition temperature is 275°C (527 °F).
Mechanical14
Torlon 4301 has a yield strength of 108 MPa (15.7 ksi) and a tensile strength of 117 MPa (17 ksi) — stronger than 98% of polymer grades. Elongation at break is 7% and the elastic modulus is 6.8 GPa (0.986 Msi).
Thermal10
Torlon 4301 is rated for continuous service to 250°C (482 °F). It conducts heat at 0.54 W/m·K (0.312 BTU/hr·ft·°F), better than 99% of polymer grades. Thermal expansion is 25 µm/m·K (13.9 µin/in·°F).
Electrical1
Torlon 4301 has an electrical resistivity of 1×10¹³ Ω·m.
Chemical & Environmental3
Corrosion resistance is excellent (85/100), better than 65% of polymer grades. UV resistance is fair.
Sustainability3
Producing a kilogram of Torlon 4301 takes about 300 MJ of energy and emits 15 kg of CO₂ — more than 97% of polymer grades. Typical recycled content is 0%.
Manufacturability7
Torlon 4301's machinability is good (55/100, worse than 64% of polymer grades); weldability not recommended (5/100); formability not recommended (5/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the polymer family
Yield strength against density for every polymer grade FabDigit runs. Torlon 4301 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with Torlon 4301
Is Torlon 4301 easy to machine?
Machines like a hard filled thermoset — rigid setups, sharp carbide or PCD tooling, light depths and air/mist cooling; graphite content is abrasive and stress-relieve/re-cure after heavy stock removal.
Can Torlon 4301 be welded?
Not melt-weldable or solvent-bondable in practice; join by mechanical fastening, press fit or high-temperature adhesives (epoxy/polyimide) on abraded, primed surfaces.
Can Torlon 4301 be formed, bent or molded?
Injection mold at 330–365 °C melt with 190–230 °C tools, thoroughly dried resin (<0.05% moisture), then post-cure several days ramping to ~260 °C to develop full strength and wear life.
Torlon 4301 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 |
|---|---|---|
| graphitewear/lubricity filler | 10 – 14 | 12 |
| PTFEfriction reducer | 2 – 4 | 3 |
| poly(amide-imide) resin (TMA/MDA based)amorphous PAI matrix | ≥ 82 (balance) |
What surface finishes work on Torlon 4301?
Naturally black, matte; can be fine-ground and lapped to tight bearing tolerances, but avoid plating/anodizing routes and note that machined surfaces bed in during initial run-in.
How much does Torlon 4301 cost?
Torlon 4301 is a high-cost polymer ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Torlon 4301 — frequently asked
What is Torlon 4301 used for?
Torlon 4301 is typically used for aerospace structural brackets, downhole tool components and high-load bushings. In short: filled PAI for stiffness; low creep at 250 °C; self-coloured black wear grade.
What is the yield strength of Torlon 4301?
Torlon 4301 has a typical yield strength of 108 MPa (15.7 ksi) and a tensile strength of 117 MPa (17 ksi) — stronger than 98% of polymer grades. Strength varies by condition: see the 7 listed tempers.
Is Torlon 4301 easy to machine?
Reasonably — machinability is rated good (55/100, worse than 64% of polymer grades). Machines like a hard filled thermoset — rigid setups, sharp carbide or PCD tooling, light depths and air/mist cooling; graphite content is abrasive and stress-relieve/re-cure after heavy stock removal.
Can Torlon 4301 be welded?
Not readily — weldability is rated not recommended (5/100). Not melt-weldable or solvent-bondable in practice; join by mechanical fastening, press fit or high-temperature adhesives (epoxy/polyimide) on abraded, primed surfaces.
What surface finishes work on Torlon 4301?
Naturally black, matte; can be fine-ground and lapped to tight bearing tolerances, but avoid plating/anodizing routes and note that machined surfaces bed in during initial run-in.
Can Torlon 4301 be formed, bent or molded?
Injection mold at 330–365 °C melt with 190–230 °C tools, thoroughly dried resin (<0.05% moisture), then post-cure several days ramping to ~260 °C to develop full strength and wear life.
What is the maximum service temperature of Torlon 4301?
Torlon 4301 is rated for continuous use to about 250°C (482 °F), and briefly to 280°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between Torlon 4301 PC and Torlon 4301 4630?
PC is the default condition — standard delivered condition — pick for all load-bearing wear parts (rings, bushings, thrust washers) needing full strength, creep and chemical resistance at 200–250 °C. 4630: maximum-lubricity PAI compound for dry-running and high-speed seal/bearing surfaces where the lowest wear rate outweighs strength. Yield strength is 108 MPa in PC versus 90 MPa in 4630.
How much does Torlon 4301 cost?
Torlon 4301 is a high-cost polymer ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sources
- Torlon Polyamide-imide Design Guide (4203L / 4301 / 4275 / 5030 / 7130) — Solvay Specialty Polymers (2021)
- Torlon PAI Processing Guide — injection molding and post-cure — Solvay Specialty Polymers (2020)
- PAI stock shape property tables (Torlon 4301 rod/plate) — Boedeker Plastics / Ensinger TECATOR (2023)
- ASTM D638 / D790 / D648 / D256 test methods — ASTM International (2022)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.