Aluminum Melting Point Guide: 6063 6061 6082 Alloy Temperatures

Aluminum Melting Point: Stuff You Actually Need to Know

At a glance
Pure Al — 660.3°C (1220°F)
6063 — 615–655°C · narrowest range, easiest to extrude
6061 — 580–650°C
6082 — 555–645°C · heavy structural
7075 — 475–635°C · wide range, hard to weld

660.3°C. That's the melting point of pure aluminum. 1220°F.

But nobody uses pure aluminum. Well, almost nobody. What you're buying is an alloy — 6063, 6061, maybe 6082. And alloys don't melt at one clean number. They melt across a range. Starts at the solidus, wraps up at the liquidus. In between, the metal's half-solid, half-liquid. Slush. Not useful.

6063 starts softening around 615°C and goes fully liquid by 655. 6061 is 580 to 650. 6082, 555 to 645. I should mention 7075 too — 475 to 635. That's a 160-degree window. Yeah. It matters.

Why the melting range matters

Actually, let me think about why.

A narrow melting range means the metal behaves. You heat it, it transitions in a tight band, you can predict what's going to happen. Predictability. That's the whole game in manufacturing. 6063 has the narrowest range of the common extrusion alloys. It's not an accident that it owns architectural profiles — window frames, curtain walls, door frames. Not the strongest. 6061 and 6082 beat it on tensile. But 6063 flows through a die better than anything else and anodizes clean, powder coats clean. No drama.

I've seen profiles come out of the press looking perfect and then the anodizing line rejects half the batch. Guess why. Thermal history.

Surface finishing

Powder coating cures at 180 to 200°C. Anodizing — acid bath, room temperature. Neither comes close to the melting point. So that's not the problem. But.

But if the billet ran too hot during extrusion. If it crept up near the solidus. Then the coating might not stick evenly. And you won't see it. Not during QC, not when you unpack the container. A year later, the coating fails. The client calls. That conversation.

So here's a thing most buyers never ask: billet temperature control.

They ask about price. Lead time. ISO certificates. All fine. But two factories both saying "6063, certified" can send you profiles that behave completely differently in your finishing line. The thermal history is invisible. Until it isn't. And by then the profiles are already cut and installed.

Extrusion temperature in practice

Alloy	Solidus	Liquidus	Application
6063	~615°C	~655°C	Window/door frames, curtain walls
6061	~580°C	~650°C	Structural frames, automotive
6082	~555°C	~645°C	Bridges, heavy structural
7075	~475°C	~635°C	Aerospace, high-end CNC

We extrude at 400 to 500°C. Way below melt. If you get near the solidus during extrusion you'll see tearing, dimensional issues. Just don't. 23 press lines, 600T to 3500T, and the one thing we stare at all day is temperature. Everything else follows from that.

Welding

6063, narrow range. Welds fine. 7075? Wide range. Hot cracking risk. Filler gets complicated. For most architectural work this isn't a problem — you're using 6063 or 6061. But if your profiles are going into a welded assembly, pick the alloy for the weld, not just the strength number on the spec sheet.

Fire resistance

The melting point answer is easy. 6063 starts at 615°C. But that's almost beside the point. Aluminum loses meaningful strength above 200°C. Way before melting. If your application sees sustained heat, aluminum might not be right.

Shipping and storage

Here's one that surprises people: shipping.

Hot container. Sitting at port. Three weeks, four weeks. Doesn't matter. You'd need 200°C before strength becomes an issue, and no container gets that hot. Rain? Aluminum doesn't rust. Just keep the profiles wrapped. Scratches during handling are the real enemy, not temperature.

I've been at this since 1994. 60,000 tons a year. 23 extrusion lines, in-house anodizing, powder coating, CNC. ISO 9001, 14001, OHSAS 18001.

But honestly. You have a question? Just ask. Faster than reading.

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