Awesome aluminium

Imagine an enormous hydraulic press squeezing out a fifty-metre long strip of piping-hot aluminium. Kind of like a play-doh press squeezing out brightly coloured spaghetti. That’s the process of making DELAKTIG. We spoke with the world’s largest aluminium extruder Sapa to find out more.

Mats Sixtensson is an applied engineer working at Sapa. Mats works with furniture “but if we’re talking about profile solutions and platforms, we can use similar functions as in the automotive and marine industries,” he says. 

Mats and his colleague Henrik Stark, the IKEA account manager at Sapa, they like the DELAKTIG project. “We like aluminium, and there is lots of aluminium in the DELAKTIG frames,” says Henrik. DELAKTIG shows what you can really achieve using aluminium profiles and platform thinking, Henrik continues, “no one has used this kind of scale in the furniture business, IKEA has really moved forward with this.” 

Sapa is the world’s largest aluminium extruder. Extrusion is the process of shaping material (by pressing it through a die), in this case aluminium, by forcing it to flow through a shaped opening in a die, which is kind of like a nozzle. And we might as well clear this up now, an aluminium profile is the result of the extrusion process.

Tom Dixon, who is working in collaboration with IKEA to develop DELAKTIG, has visited Sapa in Vetlanda, Sweden. “He was very curious about the profile and the possibilities and the whole process around this,” says Mats. Tom was ambitious with the project, together with Sapa and IKEA they have come up with ideas to solve issues and meet customer demands. Along the way, all partners have had to compromise. Right now, the DELAKTIG platform is entering the industrialisation phase, going from product development to manufacturing.

Process of making aluminium extrusions

Let’s take it from the beginning, first bauxite is taken from the ground and the pure aluminium is extracted. Aluminium is a very soft metal, so other metals are added, to make an alloy. The aluminium alloy is cast into billets that are approximately seven metres long (like an aluminium log) and then cut down to approximately 1metre in length.

This aluminium billet is then heated up to five-hundred degrees centigrade and pressed with a hydraulic press. Through a unique DELAKTIG die, in the precise shape of the pieces of the DELAKTIG profile, a 50m long aluminium profile is squeezed out.

As you know, when you squeeze play-doh spaghetti it comes out a bit curvy, same goes for aluminium, which needs to be stretched after the extrusion process.

The profile is subjected to artificial ageing by putting it in a one-hundred and eighty degree centigrade furnace for three to four hours. This tempering process hardens the metal giving it maximum mechanical properties, in other words increasing the maximum stress that can be placed on the extrusion.

Depending on what functions are needed, holes are drilled or punched in the extrusion.

Aluminium and its manufacturing process

On the drawing board, it was decided that the DELAKTIG profile would have two grooves on the underside of the sofa where you can attach a lamp or open up to other solutions that can be designed further down the line. From the outside, you can’t see these grooves, as they are on the underside of the frame.

These features are built into the extrusion in order to reduce weight, simplify assembly, add functionality and minimise finishing costs. It is taking advantage of a unique benefit of aluminium and its manufacturing process.

These features are built into the extrusion in order to reduce weight, simplify assembly, add functionality and minimise finishing costs.

Aluminium is a material that is a perfect match for modern sustainable design and production. It’s light, strong and highly recyclable, it can transform to fit any application from bridge and windows, furniture and automotive tubing.

Plus it is 100% recyclable. Aluminium can be recycled an infinite number of times with no loss of quality. Around 75% of aluminium ever produced is still in circulation. The energy needed to produce secondary aluminium is only 5% of the original energy input.

Designing for recycling and disassembly

The DELAKTIG frame is only aluminium, there is no plastic or any other material that is sometimes added to reduce costs. All the parts are easy to separate from each other. There is no additive welding, the different parts are screwed together.

The frame is designed from the beginning to be disassembled and recycled when it’s life is over. Which could be in the year 2117, some of the earliest installations of aluminium, constructed over 100 years ago, are still standing strong.

The DELAKTIG profile will be made from 50% re-melted scrap aluminium, recycled waste from other Sapa projects. The scrap is remelted at Sapa’s plant in Vetlanda, using power from their small hydro-energy plant.

Common concerns in Småland

IKEA and Sapa have a lot in common. They are both global companies based in Småland, Sweden for a start but they are also companies driven by an environmental agenda. “IKEA has a high focus on the environment and sustainability and they are communicating it quite well to their partners, they are very sharp,” says Henrik “You cannot misunderstand. They know what want in a good way.”

When working with IKEA, Sapa is keen to get into projects very early, to be able to give their solutions to design problems. Sapa doesn’t want their input to be an afterthought. “This is really important,” says Mats, “as the most influence on the price level is in the design phase.” Which is, a core principle of the IKEA Democratic Design process.

This is really important as the most influence on the price level is in the design phase.

At Sapa they are not only the world’s largest manufacturer of extrusions, they have worked a lot with product development for their customers. Their intention is to find solutions that minimise costs whilst providing the most benefits with the extrusion.

Just like IKEA is challenging the home furnishing industry in response to changing shifts in behaviour and environmental challenges, SAPA is moving forward with the application and development of aluminium, on an industrial scale. Sapa is a producer but it also has its own Research and Development company.

The finish of DELAKTIG

The finish Tom Dixon has chosen is a naturally anodised process, which creates an extra layer on the surface of the aluminium. It gives a nice appearance, whilst also making the metal more scratch resistant and protecting it from corrosion. If you look around you, maybe you see a door frame, a window or a ventilation pipe in aluminium, they’ve probably used a natural anodising process for the finish as well.

The DELAKTIG profile will be on display for the first time during the Milan furniture fair at Tom Dixon’s MULTIPLEX. In the iconic Cinema and Galleria on via Manzoni you can meet Tom Dixon, representatives from Sapa and Marcus Engman, Head of Design at IKEA.