PTFE — lowest friction coefficient of any solid material. Excellent chemical resistance. For seals, bearings, valve seats and chemical equipment.
PTFE (Polytetrafluoroethylene) per ISO 12086 is a semi-crystalline fluoropolymer with unique properties: (1) coefficient of friction 0.04-0.10 — the lowest of any solid material, (2) continuous service temperature -200 to +260 C, (3) resistance to virtually all chemicals including fumic acids, halogens and oxidising media, (4) excellent electrical insulation. Non-meltable by conventional moulding — processed by sintering and compression moulding. Reinforced grades (GF/carbon/MoS2/bronze) improve wear resistance.
| Standard Body | Designation | Country / Region | Note |
|---|---|---|---|
| ASTM D1457 | PTFE (standard) | USA | |
| ISO | ISO 13000 (PTFE) | International | |
| EN | EN ISO 13000 | EU | |
| Trade Names | Teflon PTFE (Chemours/DuPont) / Fluon PTFE (AGC) / Hostaflon TF (Hoechst) | Global | |
| Key Grades | PTFE virgin / PTFE GF25 / PTFE CF25 / PTFE+graphite / PTFE+MoS2 / Expanded PTFE (ePTFE) | Global | |
| UL | 94 V-0 (inherent) | USA | |
| FDA | 21 CFR 177.1550 (food contact) | USA | |
| NSF | NSF/ANSI 51 (food equipment) | USA | |
| JUS | PL-PTFE | Yugoslavia | Politetrafluoroetilen; JUS G.S5.080 |
| Processing | Compression moulding or RAM extrusion ONLY — cannot be injection moulded | Global |
| # | Standard Body | Designation | Country / Region | Note |
|---|---|---|---|---|
| 1 | ASTM D1457 | PTFE (standard) | USA | — |
| 2 | ISO | ISO 13000 (PTFE) | International | — |
| 3 | EN | EN ISO 13000 | EU | — |
| 4 | Trade Names | Teflon PTFE (Chemours/DuPont) / Fluon PTFE (AGC) / Hostaflon TF (Hoechst) | Global | — |
| 5 | Key Grades | PTFE virgin / PTFE GF25 / PTFE CF25 / PTFE+graphite / PTFE+MoS2 / Expanded PTFE (ePTFE) | Global | — |
| 6 | UL | 94 V-0 (inherent) | USA | — |
| 7 | FDA | 21 CFR 177.1550 (food contact) | USA | — |
| 8 | NSF | NSF/ANSI 51 (food equipment) | USA | — |
| 9 | JUS | PL-PTFE | Yugoslavia | Politetrafluoroetilen; JUS G.S5.080 |
| 10 | Processing | Compression moulding or RAM extrusion ONLY — cannot be injection moulded | Global | — |
| Element | Symbol | Min % | Max % | Typical % |
|---|---|---|---|---|
| Fluorine (all C-F bonds) | F | — | — | 76.0000 |
| Carbon | C | — | — | 24.0000 |
| Water absorption (any condition) | H2O | — | 0.0100 | — |
| Condition | Code | Rm min MPa | Rm max MPa |
Re min MPa | Re max MPa |
A₅ min % |
Z % |
KV J |
HB min | HB max | HRC min | HRC max | E GPa |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PTFE virgin (compression moulded) | STD | 20 | 30 | 14 | 24 | 200.0 | — | — | — | — | — | — | 0.5 |
| PTFE GF25 (glass-filled) | GF25 | 25 | 40 | 18 | 32 | 150.0 | — | — | — | — | — | — | 1.0 |
| PTFE CF25 (carbon-filled) | CF25 | 22 | 35 | 16 | 28 | 100.0 | — | — | — | — | — | — | 0.8 |
| Coolant | Dry; compressed air chip removal; LN2 cryogenic machining gives best results |
| Chip Formation | Extremely long waxy stringy gummy chips — worst of all polymers; cryogenic machining standard |
| Tool Material | PCD or very sharp uncoated carbide; cryogenic machining strongly recommended for production |
| Surface Finish | Ra 0.8-6.3 um (poor) — PTFE is elastically soft; better with cryogenic |