According to housekeeping guru Marie Kondo, if something isn’t useful or doesn’t “spark joy” you should get rid of it. Well one thing that sparks joy in our busy fabrication shop is aluminum extrusion. As we’ve mentioned many times, it’s incredibly versatile, which makes it useful for a host of fabrication projects. Clearly, we’re not the only ones who feel this way either, because consumption just keeps on growing.
Projections for The Extruded Aluminum Market
In 2019 the world consumed around 30 million tons of extruded aluminum. (It depends a little on whose numbers you look at, but 30 million is a good average.) That’s a colossal amount of metal, and the people who study these things forecast we’re going to use 4-5% more each year. With the power of compounding, that says by 2027 we’ll be using close to 40 million tons of aluminum extrusion each year.
The aluminum that’s used for extrusion is technically an alloy. Aluminum is made in a range of alloys described by series numbers. The alloys mostly widely used for extrusion are those from the 6000 series. These incorporate small quantities of magnesium and silicon that improve flow through the extruder and machine-ability.
Most extruded aluminum is classed as “mill finish”. That means it has the bright shiny appearance it gets on leaving the extrusion die. Some is anodized to increase corrosion resistance and a smaller proportion is powder coated.
The big markets are North America, Europe and Asia, although going forwards, most of the growth is predicted to be in Asia. And what’s it being used for? The short answer is, building and construction, automotive, consumer durables, power generation and transmission and industrial equipment. But you’d probably like a more detailed explanation.
Understanding the Versatility of Aluminum
Quick recap on what makes aluminum extrusion so useful: it’s the combination of material properties and the extrusion process. Let’s start with the properties.
Aluminum is known for being lightweight. What’s often overlooked though is that it’s very strong for its weight. A pound of aluminum is stronger than a pound of low carbon steel. This makes it very useful in structural or load-bearing applications.
Unlike steel, aluminum doesn’t rust. What happens is that it builds an oxide layer on the surface that, once present, prevents further oxidation. Scratch the surface to remove that oxide layer and another forms immediately. You could say it’s self-healing!
Thermal and electrical conductivity are both very good. That makes aluminum useful in both heat exchangers and electrical circuits.
And one more point to close out this list: it machines beautifully, especially the 6000 series alloys. Sawing to length and drilling holes are never a problem.
Turning to the extrusion aspects, this “toothpaste” process produces long lengths of uniform cross-section that have excellent dimensional stability. Aluminum stockists carry many standard sections, but should you design something custom, extrusion tooling is surprisingly inexpensive.
Design engineers love aluminum extrusion for the flexibility it offers. With a little ingenuity extruded aluminum can be used for hinges, covers, frames and brackets of every size and shape imaginable. In many applications it can substitute for steel with the advantage that it doesn’t need painting.
Major Applications for Extruded Aluminum (Where the Growth is Coming From)
The growth applications mentioned previously were:
Building and construction
Power generation and transmission
Here’s a closer look at each of these.
Building and Construction
Let’s start with the basics: aluminum extrusion is used in angle, channel and tube form for window frames, door frames, suspended ceilings and wall framing systems. Greenhouses and conservatories are farmed entirely in aluminum extrusion, and it’s often used for railings and hinges.
It’s also used where appearance is a priority. For example, wall capping systems, handrails and even columns can be produced from aluminum extrusion. And last, there’s a whole category of “infrastructure” applications. These range from street signs to bridges. Yes, bridges are sometimes assembled from aluminum extrusion before being moved into place.
This should help clarify why Asia is such a growth market: there’s a lot of construction going on, and extrusion is fast and easy to work with, strong and cost effective.
As readers probably know, lightweighting is a priority in the automotive world, and aluminum has a big part to play as a substitute for steel. A particular, and growing, application area is in electric vehicles (EVs). As batteries are extremely heavy it’s vital to save as much weight as possible elsewhere. If anything, a move to EVs is only going to increase demand for aluminum extrusion.
But let’s broaden the definition of automotive beyond cars and trucks. Trailers, from horse trailers to those hauled cross-country by Class 8 trucks, all make extensive use of aluminum extrusion. Saving weight and adding strength are the two reasons designers of parts for these applications like to use aluminum.
Air conditioning and refrigeration are projected to drive a big increase in demand for aluminum extrusion. Again, much of this will come from Asia. That’s because incomes are rising there and they like to stay cool and refrigerate their food as much as we do.
Power generation and transmission
Solar power installations are multiplying rapidly. That’s the case in Europe and the US, but especially in Asia where demand for electricity is rising quickly. Aluminum extrusion is the idea material for framing those acres of solar panels as it’s lightweight, (so it can go on rooftops,) easily cut to size, and doesn’t need painting or other corrosion protection.
Solar probably won’t replace conventional power generation plants any time soon though, and the power those produce is carried through cables strung from transmission pylons. Aluminum is a good choice of material for pylons for the same reasons it makes sense in solar panels: it’s lightweight and resists corrosion.
We’ve been saying this for a long time: aluminum extrusion makes a lot of sense in a host of industrial applications. It’s idea for machine guards, screens, carts and frames because it’s lightweight, easy to work and can have grooves and other features incorporated that simplify assembly. Plus, it doesn’t rust so you won’t have to paint it. Manufacturing isn’t going away, in fact it appears to be rebounding, so there’s likely to be strong demand for extrusion from this sector for a long time.
We’re Ready for Growth
Walk through our shop and you’ll see we use a lot of extruded aluminum. Judging by the growth projections, it seems we could be using more in the future. You’ll also see we try hard to keep things clean and tidy and avoid hanging on to stuff we don’t need. We like the 5S housekeeping methodology – Sort, Set, Shine, Standardize, Sustain – but the Konmari Method™ has a lot going for it too. After all, there’s no doubt that aluminum extrusion sparks joy for us.