Electrical conductivity chart.
How well each material we offer carries current, against copper at 100% IACS — with brass, titanium and nickel alloys for comparison. Sometimes you want it high, sometimes low: a bus bar wants every bit of conductivity, a spot weld wants resistance, and a standoff wants none at all.
| Material | Offered as | % IACS | MS/m | Resistivity | Fit |
|---|---|---|---|---|---|
| C110 copper, half hard | Reference | 101 | 58.6 | 1.71 µΩ·cm | — |
| C260 cartridge brass, half hard | Reference | 28 | 16.2 | 6.16 µΩ·cm | — |
| C360 free-cutting brass | Reference | 26 | 15.1 | 6.63 µΩ·cm | — |
| 1100-H14 | Sheet stock | 59 | 34.2 | 2.92 µΩ·cm | — |
| 6061-T6 | Sheet stock · CNC | 43 | 24.9 | 4.01 µΩ·cm | — |
| MIC-6 cast plate | Sheet stock | 36 | 20.9 | 4.79 µΩ·cm | — |
| 5052-H32 | Sheet stock | 35 | 20.3 | 4.93 µΩ·cm | — |
| 7075-T6 | Sheet stock · CNC | 33 | 19.1 | 5.22 µΩ·cm | — |
| 3003-H14 | Reference | 43 | 24.9 | 4.01 µΩ·cm | — |
| 2024-T3 | Reference | 30 | 17.4 | 5.75 µΩ·cm | — |
| Magnesium AZ31B-H24 | Reference | 18 | 10.4 | 9.58 µΩ·cm | — |
| A1008 cold rolled | Sheet stock | ≈ 12.1 | 6.99 | 14.3 µΩ·cm | — |
| A1008 electro-galvanized | Sheet stock | ≈ 12.1 | 6.99 | 14.3 µΩ·cm | — |
| G90 galvanized | Sheet stock | ≈ 12.1 | 6.99 | 14.3 µΩ·cm | — |
| A36 HR pickled & oiled | Sheet stock | 11.5 | 6.67 | 15 µΩ·cm | — |
| A36 mill finish | Sheet stock | 11.5 | 6.67 | 15 µΩ·cm | — |
| HSLAS Grade 50 | Sheet stock | ≈ 10.1 | 5.88 | 17 µΩ·cm | — |
| Spring steel 1075 / 1095 | Sheet stock | ≈ 9.58 | 5.56 | 18 µΩ·cm | — |
| AR500 | Sheet stock | ≈ 7.84 | 4.55 | 22 µΩ·cm | — |
| Corten (weathering) | Sheet stock | 7.5 | 4.35 | 23 µΩ·cm | — |
| 1018 cold drawn | Reference | ≈ 10.8 | 6.29 | 15.9 µΩ·cm | — |
| 4140 annealed | Reference | 7.84 | 4.55 | 22 µΩ·cm | — |
| CP titanium Grade 2 | Reference | 3.22 | 1.87 | 53.5 µΩ·cm | — |
| Ti-6Al-4V (Grade 5) | Reference | 1.01 | 0.585 | 171 µΩ·cm | — |
| 304 | Sheet stock | 2.39 | 1.39 | 72 µΩ·cm | — |
| 316 | Sheet stock | 2.33 | 1.35 | 74 µΩ·cm | — |
| 430 | Reference | 2.87 | 1.67 | 60 µΩ·cm | — |
| 303 | Reference | 2.39 | 1.39 | 72 µΩ·cm | — |
| 17-4 PH, H900 | Reference | 2.24 | 1.3 | 77 µΩ·cm | — |
| Monel 400 | Reference | 3.37 | 1.96 | 51.1 µΩ·cm | — |
| Monel K-500 | Reference | 2.8 | 1.63 | 61.5 µΩ·cm | — |
| Inconel 600 | Reference | 1.67 | 0.971 | 103 µΩ·cm | — |
| Inconel 718 | Reference | 1.38 | 0.8 | 125 µΩ·cm | — |
| Inconel 625, annealed | Reference | 1.34 | 0.775 | 129 µΩ·cm | — |
| Hastelloy C-276 | Reference | 1.33 | 0.769 | 130 µΩ·cm | — |
| PA-11 (HP MJF) | 3D printing | — | 10⁻¹⁰–10⁻¹⁰ | 10¹²–10¹² Ω·cm | — |
| PA-12 (HP MJF) | 3D printing | — | 10⁻¹²–10⁻¹² | 10¹⁴–10¹⁴ Ω·cm | — |
| PA-12 glass bead (HP MJF) | 3D printing | — | 10⁻¹²–10⁻¹² | 10¹⁴–10¹⁴ Ω·cm | — |
| Nylon 6/6 (dry) | Reference | — | 10⁻¹²–10⁻¹⁰ | 10¹²–10¹⁴ Ω·cm | — |
| Acetal homopolymer (Delrin) | Reference | — | 10⁻¹³–10⁻¹² | 10¹⁴–10¹⁵ Ω·cm | — |
| ABS | Reference | — | 10⁻¹⁴–10⁻¹³ | 10¹⁵–10¹⁶ Ω·cm | — |
| UHMW polyethylene | Reference | — | 10⁻¹⁵–10⁻¹² | 10¹⁴–10¹⁷ Ω·cm | — |
| PEEK (unfilled) | Reference | — | 10⁻¹⁴–10⁻¹⁴ | 10¹⁶–10¹⁶ Ω·cm | — |
| Polycarbonate | Reference | — | 10⁻¹⁴–10⁻¹⁴ | 10¹⁶–10¹⁶ Ω·cm | — |
| Acrylic (PMMA) | Reference | — | 6.3×10⁻¹⁵–10⁻¹⁴ | 10¹⁶–1.6×10¹⁶ Ω·cm | — |
| PTFE (Teflon) | Reference | — | 10⁻¹⁶–10⁻¹⁵ | 10¹⁷–10¹⁸ Ω·cm | — |
| Carbon fiber laminate (quasi-isotropic) | Reference | — | 5×10³–5×10⁴ | 2×10⁻³–2×10⁻² Ω·cm | — |
| G-10 / FR-4 laminate | Reference | — | 10⁻¹²–10⁻¹¹ | 10¹³–10¹⁴ Ω·cm | — |
Pick the conductivity for the job.
Conductivity is not a score where higher wins. A part that carries current wants it high; a part that has to make heat, weld easily or keep two circuits apart wants it low.
Among the metals we offer, 1100-H14 conducts best at 59% IACS — about 25 times 304 stainless at 2.4%. Copper is the reference at 101%. Our MJF nylons are insulators, conducting about 10²⁰ times less than copper. Choose a use below to see which materials fit it on the chart.
High conductivity
Low — or none
The surface decides contact
Anodizing and powder coat are insulators. A grounded enclosure needs bare or conductive-coated contact points — mask them before finishing, or specify chromate conversion coating.
Heat treatment moves it
Alloying and precipitation scatter electrons, so 6061-T6 conducts less than 1100, and the same alloy changes with temper. Aluminum shops use an eddy-current conductivity check to confirm temper.
Galvanic corrosion is separate
Which metal corrodes in a mixed joint depends on electrode potential, not conductivity. Carbon fiber conducts and is noble, so it corrodes aluminum it touches — insulate the joint.
% IACS, MS/m and resistivity.
% IACS is conductivity as a percentage of annealed copper: 100% IACS = 58.0 MS/m = a resistivity of 1.7241 µΩ·cm at 20 °C. To convert: % IACS = 172.41 ÷ resistivity in µΩ·cm.
The default scale shows the metals in % IACS on a log axis. All · S/m adds the plastics: their conductivity is lower than copper's by a factor of 10²⁰ or more, so they sit at the far left as insulators. The calculator gives the resistance of a bar, R = ρ·L ÷ (t·w), and the heat it makes at your current, I²R — at 20 °C and before contact resistance at the joints.
For bus-bar sizing against a temperature rise, see the electrical conductivity guide.
Where the numbers come from.
- IEC 60028 — International standard of resistance for copper (100% IACS = 58.0 MS/m = 1.7241 µΩ·cm at 20 °C) — IEC
- ASTM B193 — Resistivity of Electrical Conductor Materials — ASTM International · four-wire resistance method
- ASTM E1004 — Determining Electrical Conductivity Using the Electromagnetic (Eddy Current) Method — ASTM International
- Physical properties of aluminium alloys (Aluminum Association typical conductivity, reprinted table) — TubingChina · source
- AMS 4008 AlMn1Cu 3003-H14 sheet — Referans Metal · source
- 7075-T6 / T651 technical data sheet (Kaiser Aluminum) — Protolabs · source
- Cast tool & jig plate: conductivity “36% of copper” — Speedy Metals · source
- AZ31B magnesium — MakeItFrom · source
- C11000 electrolytic tough pitch copper — Copper Development Association · source
- Copper alloy designations and properties — Copper Development Association · source
- MA36B / C36000 free-cutting brass — Fisk Alloy · source
- Carbon steel grade 1010 data sheet — Elgin Fasteners · source
- A36 steel — Wikipedia · source
- Alloy steel grade 4140 fact sheet — Elgin Fasteners · source
- SAE-AISI 1080 vs ASTM A227 spring steel — MakeItFrom · source
- A588 weathering steel product guide — OnlineMetals · source
- Zinc, Goodfellow foil product data (resistivity 5.8–5.9 µΩ·cm) — Sigma-Aldrich · source
- ATI 302 / 304 / 304L / 305 technical data sheet — ATI · source
- 316L alloy data sheet — Combined Metals · source
- 303 stainless data sheet — United Performance Metals · source
- ATI 430 technical data sheet — ATI · source
- ATI 17-4 technical data sheet — ATI · source
- Titanium Grade 2 specification sheet — Arnold Magnetic Technologies · source
- Ti-6Al-4V data sheet — United Performance Metals · source
- INCONEL alloy 600 technical bulletin — Special Metals Corporation · source
- INCONEL alloy 625 technical bulletin — Special Metals Corporation · source
- INCONEL alloy 718 technical bulletin — Special Metals Corporation · source
- MONEL alloy 400 technical bulletin — Special Metals Corporation · source
- MONEL alloy K-500 technical bulletin — Special Metals Corporation · source
- Hastelloy C276 — Fort Wayne Metals · source
- HP 3D High Reusability PA 12: UL 94 and UL 746A certification note — HP, via Sculpteo · source
- HP MJF PA 11 UL Blue Card — HP / UL, via Sculpteo · source
- Nylon PA 12 Glass Beads technical data sheet — Weerg · source
- Zytel 101L NC010 nylon 6/6 data sheet (IEC 62631-3-1) — DuPont, via Protolabs · source
- Delrin 150 acetal homopolymer data sheet — Plastics International · source
- VICTREX PEEK 450G datasheet — Victrex · source
- Teflon typical properties — All Seals · source
- Makrolon 2805 polycarbonate data sheet — Covestro, via Protolabs · source
- Handbook of Plastics, appendix D: electrical properties of resins and compounds — GlobalSpec · source
- Plexiglas acrylic sheet data — The Gund Company · source
- TIVAR 1000 UHMW-PE colors technical data sheet (IEC 62631-3-1) — Mitsubishi Chemical Advanced Materials · source
- T700S carbon fiber data sheet (fiber resistivity 1.6×10⁻³ Ω·cm) — Toray · source
- Understanding differences in welding steel vs aluminium — AHSS Insights · source
- Is the anodic coating a good electrical insulator? — Southern Aluminum Finishing · source
- Anodizing reference guide — Aluminum Anodizers Council · source
- Copper for Busbars — Copper Development Association · bus-bar sizing, temperature rise and joint design
Typical values at 20 °C. Values marked ≈ are typical for the steel type rather than published for that exact grade.