Torlon 4301 4203L
Reinforced grade
4203L = torlon 4203L
Sibling unfilled grade — pick when maximum toughness, elongation and electrical insulation matter more than wear resistance or stiffness.
Values for the 4203L condition
Other Torlon 4301 grades and fills
Torlon 4301 is listed in 7 conditions; see the grade overview at Torlon 4301.
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 | — |
4203LThis page 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 | — |
What is Torlon 4301 4203L?
Torlon 4301 4203L is Torlon 4301 in the 4203L grade — sibling unfilled grade — pick when maximum toughness, elongation and electrical insulation matter more than wear resistance or stiffness. Torlon 4301 4203L has a yield strength of 108 MPa (15.7 ksi) and a tensile strength of 192 MPa (27.8 ksi) — stronger than 98% of polymer grades. Elongation at break is 15% and the elastic modulus is 4.5 GPa (0.653 Msi). Torlon 4301 4203L has a density of 1.42 g/cm³ (0.0513 lb/in³), heavier than 83% of polymer grades. Its glass-transition temperature is 275°C (527 °F). PC is the default condition FabDigit quotes; 4203L is available on request or by drawing note.
Advantages
- 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
- Low, predictable mold shrinkage — 0.3%, better than 90% of polymer grades
- Stiff — 4.5 GPa (0.653 Msi), better than 88% of polymer grades
- Conducts heat well — 0.26 W/m·K (0.15 BTU/hr·ft·°F), better than 77% 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 — 1.42 g/cm³ (0.0513 lb/in³), worse than 83% of polymer grades
Torlon 4301 4203L properties
Typical room-temperature values for Torlon 4301 4203L; 15 are specific to this condition. Other listed values are Torlon 4301 reference data and may not represent this condition. Bars are the position among polymer grades.
Physical4
Torlon 4301 4203L has a density of 1.42 g/cm³ (0.0513 lb/in³), heavier than 83% of polymer grades. Its glass-transition temperature is 275°C (527 °F).
Mechanical14
Torlon 4301 4203L has a yield strength of 108 MPa (15.7 ksi) and a tensile strength of 192 MPa (27.8 ksi) — stronger than 98% of polymer grades. Elongation at break is 15% and the elastic modulus is 4.5 GPa (0.653 Msi).
Thermal10
Torlon 4301 4203L is rated for continuous service to 250°C (482 °F). It conducts heat at 0.26 W/m·K (0.15 BTU/hr·ft·°F), better than 77% of polymer grades. Thermal expansion is 31 µm/m·K (17.2 µin/in·°F).
Electrical1
Torlon 4301 4203L 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 4203L 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 4203L's machinability is good (65/100, better than 66% of polymer grades); weldability not recommended (5/100); formability not recommended (5/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with Torlon 4301 4203L
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.
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.
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) | — |
Torlon 4301 4203L — frequently asked
What is Torlon 4301 4203L used for?
Torlon 4301 4203L 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 4203L?
Torlon 4301 4203L has a typical yield strength of 108 MPa (15.7 ksi) and a tensile strength of 192 MPa (27.8 ksi) — stronger than 98% of polymer grades. Strength varies by condition: see the 7 listed tempers.
Is Torlon 4301 4203L easy to machine?
Reasonably — machinability is rated good (65/100, better than 66% 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 4203L 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 4203L?
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 4203L 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 4203L?
Torlon 4301 4203L 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.
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. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.