Does Aluminum Conduct Electricity?

61% IACS. That's aluminum's electrical conductivity compared to copper.

Yes, it conducts. Very well. But the number you care about depends on how you measure it.

By volume, copper is king — 100% IACS is the baseline. Silver is 105%, gold 70%, aluminum 61%. Steel? About 10%. Steel doesn't count.

Now flip the comparison. By weight, aluminum carries twice as much current as copper for the same mass. This matters when weight is your enemy — overhead power lines stretching for miles, EV battery components, solar mounting hardware. Every kilogram saved is money saved. That's why you see aluminum up on transmission towers, not copper.

The physics is simple: free electrons. The same thing that makes aluminum electrically conductive also makes it thermally conductive. The two properties are linked. That's why aluminum heat sinks exist — if a metal conducts electricity well, it probably dissipates heat well too.

Heat sinks — where extrusion shines

6063 is the workhorse. Thermal conductivity around 200 W/m·K. It's not the most conductive alloy — pure aluminum beats it — but pure aluminum is too soft to extrude into thin fins. 6063 flows through a die beautifully. You can push it into complex geometries, huge surface area for heat dissipation. The tradeoff is worth it: a little less conductivity for dramatically better formability.

6061 tells a different story. Only about 40% IACS, but stronger. If your part needs to carry current and take mechanical load — busbars in switchgear, substation connectors, EV charging infrastructure — 6061 makes sense. It's not the best conductor, but it won't bend under load.

6082 sits around 42%. Similar ballpark. 7075, forget it — 33%. Don't use 7075 for anything electrical unless strength is the only requirement and conductivity doesn't matter at all.

Alloy conductivity at a glance

Where anodizing gets people into trouble

Aluminum forms an oxide layer naturally in air. Thin, transparent, non-conductive. Anodizing thickens that layer — great for corrosion, but it's an insulator. I've seen customers order anodized profiles for electrical applications and then call us confused. The whole part is coated. Nothing conducts.

Three fixes: mask the contact areas before anodizing, machine the coating off at contact points, or skip anodizing and use chemical conversion coating instead. We handle all three. 

Powder coating is even worse — fully insulating. Same rule.

For heat sink applications, clear or black anodizing is still fine. The anodic layer is so thin it barely affects thermal performance, and the corrosion protection is worth it.

Aluminum vs copper

Copper is better by volume. No argument. But it's three times heavier, three to four times more expensive, and you can't extrude it into complex profiles. If space is so tight that every cubic millimeter of conductivity counts, use copper. For everything else where weight, cost, or shape matters — aluminum.

Quick questions I get asked

Q:Does aluminum beat steel as a conductor?

A:About six times better. Steel is not an electrical material. End of story.

Q:Can you wire a house with aluminum?
A:Yes, people did. 1960s and 70s it was everywhere. Still code-approved today with the right alloy — AA-8000 series. But copper took over for residential. Not because aluminum fails, but because it expands and contracts more with temperature, loosening terminals over time. Proper installation solves it, but electricians prefer copper, and habits stick.

Q:Is melting point related to conductivity?

A:Loosely. High electrical conductivity tends to come with high thermal conductivity — related physics. But the melting point number itself isn't directly connected. We wrote a whole other article about that if you want the details.

Q:Which alloy for a heat sink? 

A:6063-T5. Best balance of conductivity, extrusion quality, and cost. If you need more strength, 6061-T6 works but you'll lose some thermal performance.

Q:Will powder coating affect conductivity? 

A:Yes — fully insulating. Mask contact points or machine them clean after coating. 

Q:You're sourcing aluminum profiles for an electrical or thermal application?
A:Figure out what matters: conductivity, strength, or both. 6063 for heat sinks, 6061 or 6082 for structural. Tell us where contact points need to stay bare. 

We've been doing this since 1994. 6063, 6061, 6082 — all in-house. Anodizing, powder coating, CNC, electrical contact masking — one factory. 23 lines. 60,000 tons a year. ISO 9001, 14001, OHSAS 18001.

Send the drawings. We'll figure out the alloy.

— Guangdong Jiahua Aluminum Co., Ltd., Foshan, China