Interview: Tritone on its MoldJet technology and DOMINANT 3D printing platform

"This is for industrial additive manufacturing."

by Laura Griffiths

14 February 2020

14:36

Tritone's DOMINANT AM platform.

Have you ever heard of the “diabolus in musica”? Translated as “the devil in music”, it was the name given to a musical interval in the early 18th century, characterised by its three adjacent whole tones (or six semitones), jarring nature, and rarely used in musical notation due to the unconventional, suspense-filled sound it created. To music theorists, it’s more formally known as a tritone.

Fast forward a few centuries to Formnext 2019 and that word has an entirely different meaning in the context of manufacturing as a new Israel-based additive manufacturing (AM) company that's adopted the moniker, introduced the world’s AM contingent to its DOMINANT platform – another nod to the musical lexicon, as Tritone’s VP Products and Business Development, Omer Sagi shared on a tour of the company’s booth. Fortunately, the reception on the show floor was a much more welcome one than that of the tritones of the 18th century, and TCT was all ears.

"It's a completely new technology," Sagi says, ushering towards the mammoth AM system which drew a lot of attention during my visit on the opening day of the Frankfurt event. "[There's] a lot of excitement. Everybody that comes here, that already knows the market, [asks] is it binder jet? Is it a laser? It's none. It's a completely new technology and I think this is what's so exciting."

The DOMINANT is a beast of a machine with a footprint of 3200 x 2200 x 1900 mm, distinguished by its irregular hexagon shape. Requiring no specific operating conditions, it feels like an AM lab unto itself, encased by clear panels so you can see exactly what's going on inside, and encompassing multiple process steps which go from mould making to material deposition and layer inspection across a carousel.

The technology within those walls is called MoldJet, a new powderless process that leverages ink jetting to produce high resolution parts in a range of metal alloys at what Tritone says is "industrial speed", equating to a throughput of up to 1,600 cc/hour. Contrary to conventional printing technologies, the machine prints the mould rather than the part itself. It's reminiscent of the eggshell moulding/3D printing style concept we saw from start-up Collider back in 2017, but rather than printing the entire mould and injecting material into the cavity, Tritone does it layer by layer.

Parts printed on the DOMINANT AM system.

The virtuoso element comes through in the DOMINANT's own six semitones; a succession of six trays which act independently and simultaneously to one another for continuous production. The technology works by jetting a thin layer of proprietary material from a high-resolution print head to create an outer mould. A specially formulated metal or ceramic paste is then deposited into the void while a precision blade wipes away any excess to leave a smooth layer. The material then undergoes a thermal processing step to harden followed by inspection to analyse layer quality. Any layers that don't make the cut are removed and the step is repeated without disrupting the rest of the process. Once finished, parts are taken from the tray and placed into an ultrasonic bath which dissolves the mould material to leave a robust green part, ready for the final sintering step. The result is a collection of parts boasting a smooth surface quality and fine detail whether they're 2mm or 350mm in size.

"We can do prototypes but you don't buy these kind of machines to prototype," Sagi explains, elaborating on the machine's industrial focus. "This is for industrial additive manufacturing. It can be in almost every industry from aerospace to automotive to tools to consumer electronics."

Tritone was founded in 2017, backed by Israeli private equity group Fortissimo Capital Fund - yet another musical nod - and formed of experts in industrial textile printing, inkjet technology, software and business development. The company's location is equally significant with Israel hardly short on AM innovation; Xjet's Additive Manufacturing Centre is just around the corner and Stratasys' HQ just a short 30-minute drive away.

"Israel is quite known for the printing industry," Sagi comments. "We have a very experienced team coming from 3D printing, the printing industry and also people that already have […] a very strong track record. It's a good mix of technical people, business people [with] a wide view of the market and needs."

On the booth, I'm shown displays chock full of part samples from the tiniest of detailed components to large tools for aerospace. Sagi says the company printed thousands of these samples in just the last two months leading up to the show alone, illustrating a broad application scope afforded by a substantial build volume (each tray has a max build size of 400 x 240 x 120 mm and can handle different build files) and material flexibility.

"You hardly see any industry that needs only big parts, only small parts and now we allow you the freedom to do both in one go," Sagi explains. "In many cases, you see people go to a technology because they need fine details. So, they compromise on the material, or they need specific materials so they compromise on the shape, but here we can get both at the same time. This is the key. It can be big or small, fine detail and then you can choose the material that is the most relevant for the application."

Tritone's software platform.

The material handling is one of Tritone's biggest USPs. The metal paste is housed inside a sealed tube which can be easily slotted into the machine for quick changeovers and to eliminate material contact with the operator. A wide range of materials have been tested so far including stainless steels, tool steels, high temperate alloys, titanium, copper-based and ceramic, and once sintered, Tritone says parts can deliver a density up to 99% with a quality on par with that of MIM. The high resolution and smooth finish is down to the accuracy of the outer mould material. In terms of future materials development, Tritone says if a material can be formulated into a paste, theoretically, it can be used in the machine, while the ability to use common MIM materials rather than AM-specific powders could also bring costs down.

The other major feature of Tritone's technology is inspection. Parts are analysed in real-time using a high-resolution camera to check for any defects and ensure that the printed part matches the design intent. "We inspect every layer on every tray," Sagi confirms. Builds are compared to the design file and erroneous layers are removed using a milling station and rebuilt before moving on to the next.

Print progress can be viewed via live imaging which feeds back to Tritone's software. The company offers a print management platform which looks after job set up, management and real-time reporting on each job file. However, Sagi adds that, rather than reinvent the wheel, the company is open to working with software experts within the industry to expand and build on tools such as shrinkage calculation.

"We use some external software but most of the core technology is developed internally," Sagi says. "The industry has a lot of good things to offer. Of course, if there is something that we can use, externally, which was developed by experts, then there's no doubt that we will be leveraging for our purposes."

The DOMINANT is not available on the market just yet but the company says it is working on installing the machines with early stage partners in Europe and Israel over the next few months. A commercial launch is expected towards the end of this year.

by Laura Griffiths

14 February 2020

14:36

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