Directional forces: A look at Anisoprint’s composite 3D printing technology

It’s hard,” said Anisoprint CEO Fedor Antonov, “but it’s only possible to convince people through business cases; show that, using this process [or] this material, the characteristics, whether it’s cost or time, are twice or three times better, not just 10% or 20% because no one would be interested.

“That’s what the whole additive manufacturing (AM) industry is fighting for, so we, altogether, grow the market. We try to find new niches, new business cases, bigger and bigger and bigger business cases, to get, to capture, to disrupt more of the traditional manufacturing.”

That might well have been an excerpt from Antonov’s acceptance speech as his company fought o  the likes of HP, AddiFab and Velo3D to take home the 2019 TCT Hardware Award for non-polymer systems on a night where it seemed each winner chose to pay tribute, or issue a rallying cry, to the rest of the industry. Turns out, the hours spent in conversation with TCT Show visitors earlier that day left Antonov bereft of little more eloquence as he excitedly, and repeatedly, gave thanks before delivering a high five to every incumbent of every seat at his table. Fortunately, we were one such conversation.

At the back of Ansioprint’s TCT Show stand was one of the company’s Composite Fiber Coextrusion (CFC) desktop machines – Anisoprint currently offers the Composer A4, with a build platform of 297 x 210 x 145 mm, and the Composer A3, with a build platform of 420 x 297 x 210 mm. Both machines are equipped with two spools of  lament being fed through a single, heated dual nozzle extruder. On the right, a spool of reinforced fibre passes through a cutter and into the heated extruder head where it joins a thermoplastic polymer. The extruder then lays down the fibre and thermoplastic material to build up parts, with the layer scheme of the part orchestrating both nozzles to deposit material once at a time several times per layer.

“The idea is that you take a thermoplastic material, bond stiff and strong fibres in one composite material, and this material is an order of magnitude stronger than any plastic,” Antonov said. As ever with 3D printing technologies, most of the value comes in the design of the part. That’s true of composites too, which, Antonov told a TCT Introducing Stage audience, are best suited to latticed structures because their key properties are directionally dependant due to their natural anisotropy, similar to how wood is stronger along the grain than across it. When working with composite materials on traditional manufacturing technologies, where they are hamstrung by the design limitations, it’s common for engineers to attempt to make a quasi-isotropic laminate and ‘squeeze’ the material properties in different directions. That can compromise the quality of the material.

“But in lattices where you have ribs – a rib is a 1D structure – you have the fibre along the rib and it only has stresses and internal forces along the rib,” states Antonov. “That’s why our approach is called Anisoprinting because we believe that anisotropic properties of material are not a disadvantage, but are a big advantage, because if you have control of the anisotropic properties, you can focus them in the right direction. You can not only optimise the shape of the part, but also the internal structure of the part.”

CFC allows users to implement four different types of fibre infill in their parts, as displayed by four sample parts manufactured by Schunk Carbon Technology on Anisoprint’s TCT Show stand (shown below). Among that selection is a solid infill part, where solid fibres sit next to each other in different directions, or three lattice options: Anisogrid reinforced infill, rhombic reinforced infill, and reinforced perimeters. Meanwhile, Antonov spotlighted some industrial applications during his talk including a clevis for a dairy company’s production line which moved bottles around and needed to be able to resist hydrogen peroxide and an aircraft seat support which is projected to save up to $50,000 a year in cost thanks to a 40% weight reduction.

Notably, these are components that would typically be made in metal with solid infills, and, as per the t-shirts adorned by the Anisoprint team at TCT Show, the company is all about stopping ‘metal thinking’.

“Metal thinking is what engineers do with composites today,” Antonov said. “They try to make this quasi isotropic thing which would work almost exactly as a metal plate would and they mill it and drill it and cut it, damaging the fibres, introducing defects inside like delamination. We believe this is the wrong way of thinking. They shouldn’t do that with composite material, you should keep fibres intact for them to work properly.”

Anisoprint, a 17-strong team made up mostly of engineers, knows that better than anyone. The company oversees the development of fibres for its CFC technology and currently offers both carbon, for high-performance applications, and basalt, as a cheaper option. More fibres are being worked on at its R&D base in Russia. Meanwhile, most machine sales are done through regional resellers. Composer platforms have been available in Germany since Formnext 2018; in France, Belgium and the Netherlands since spring; and in the UK as of September when iMakr was announced as a distribution partner. Anisoprint deploys a team of application engineers to work closely with these partners and aid customers as they get to grips with CFC.

The company sees suitable applications in several vertical markets, with jigs, fixtures and tooling being highlighted as the obvious low hanging fruit and spare parts also being touted in the mobility sector. But Anisoprint wants to cater for bigger parts too and this autumn will unveil the Composer A2. It will come with an increased build platform to satisfy the industry demand for larger printed parts, advanced features to guarantee superior productivity and, such is the nature of carbon fibre reinforcement, should actually be easier to use.

“The bigger the part, the bigger the savings. Everything is related to volume,” Antonov said. “You can make people interested with these small pieces, but they are much more interested when they start talking about bigger parts. And, actually, the [CFC] technology works much better on bigger parts, because the fibre has a certain layer thickness tolerance, there’s still some limitations when you try to place the fibre in a tiny part.

“In this range from 300mm to 1m, there is no real offer,” he continued, in reference to composite machines currently on the market. “You might have large metal printers like Electron Beam or something like that, but that’s metal. [Manufacturers] do one metre, one and a half metre tools with metal, but to move those tools around the shop you need cranes or trolleys, and that’s where composites can bring the extra value. It will have the same stiffness and strength as metal, but many times lighter so you can carry it easily.”

Further along Anisoprint’s R&D roadmap, bigger machines again will be introduced, more and more fibres too, and, in the company’s ideal world, composite manufacturing will no longer be restrained by ‘metal thinking’.

In years to come, Anisoprint wants to see composite moulds carried across shop floors, rather than metal ones trolleyed; it wants to see latticed components in the cabin of aeroplanes, rather than solid blocks of material; it wants to see Antonov back up on stage, with a heart full of thanks, and a hand full of a TCT Application Award.

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