Arevo Labs 3D printer uses a robotic arm to make a carbon fiber part.
At REAL 2016, a new contender stepped into the ring to win “Best Pitch” at the event’s REAL Deal Startup Competition. Presenting its unique brand of composite 3D printing materials to a panel of venture capitalists yesterday, Silicon Valley’s Arevo Labs ultimately won the judges over, beating out Lucid VR's stereoscopic virtual reality cameras, Minds Mechanical’s metrology-based software solutions and UNYQ’s 3D-printed prosthetic covers. The reason for this may have been due to how far along Arevo Labs has gone with carbon fiber–reinforced polymers, which CEO Hemant Bheda claims can produce parts with the strength of titanium at one-third the weight.
It was Massachusetts-based MarkForged that rocked the manufacturing scene at SOLIDWORKS World 2014 with the release of the Mark One carbon fiber 3D printer, since upgraded to the Mark Two. Using their proprietary continuous filament fabrication (CFF) process, the Mark Two is capable of printing strands of continuous carbon fiber within nylon parts, resulting in one-off parts with a higher strength-to-weight ratio than aluminum. For the past two years, it seemed as though MarkForged was the undisputed champion of desktop composite 3D printing.
Four different filaments from Arevo Labs made from varying combinations of PEEK, PAEK and PARA polymers as well as carbon fiber, glass fiber and carbon nanotubes. (Image courtesy of Arevo Labs.)
Currently, Arevo Labs manufactures six different filaments for fused deposition modeling (FDM) 3D printing, all of which are some combination of polyetheretherketone (PEEK), polyaryletherketone (PAEK) and polyarylamide (PARA) polymers blended with carbon fiber, glass fiber and carbon nanotubes. Their Quantevo line is available in pure PAEK, as well as in carbon fiber– and carbon nanotube–reinforced varieties. Although carbon fiber increases the strength and stiffness of the material, carbon nanotubes give the filament electrostatic discharge of 10E6 to 10E9 ohms/square, making it useful for electronic and aerospace applications.
Fuel intake runners 3D printed with Arevo Labs’ PEEK filament for automotive engineer Matti Holtzberg for the Polimotor 2 Project. (Image courtesy of Arevo Labs
Their Katevo line, too, is available with carbon fiber reinforcement, but this material is a PEEK composite, engineered for temperature, dynamic fatigue and chemical resistance. This, Arevo Labs envisions, makes Katevo ideal for use in highly toxic environments, as in the oil and gas industry. Xanevo PARA, their final filament line, has been engineered for strength, stiffness and reduced thermal expansion. The ideal use case for Xanevo, according to the firm, is for single-use medical tools that require greater strength than polyamide (nylon).
Although the Mark Two can reinforce printed parts with secondary materials like Kevlar and fiberglass, in addition to carbon fiber, the outer shells of these parts are made of nylon. What sets Arevo Labs apart from MarkForged, their biggest competition (according to Bheda at REAL 2016), is the use of these ketone polymers, which the startup claims can outperform materials like nylon in terms of strength-to-weight ratio and corrosion resistance. In turn, Bheda claims that they can produce parts with the strength of titanium and not just greater than aluminum, as is the case with MarkForged’s CFF process.
Arevo Labs further differentiates itself from the competition through the process by which their composites are printed. One of the strengths of CFF is that continuous strands of fiber are laid down within a part, one flat layer at a time, increasing its strength when compared to objects made with chopped reinforcement fibers. As a result, the actual reinforcement material cannot be printed into the same complex geometries typically made possible with 3D printing.
The filaments from Arevo Labs, on the other hand, are encapsulated in a polymer matrix and can be 3D printed on most FDM machines capable of reaching the necessary temperatures. This is also a significant advantage that their materials have over other composites on the market. Whereas most FDM filaments use an epoxy as a binder, to fuse the primary polymer and the reinforcing material together, the range from Arevo Labs is bonded through the polymer itself.
What may not be initially clear, when it comes to 3D printing with composite filaments, is that the orientation of the reinforcement fibers can be essential to the physical properties of a fabricated object. Therefore, the typical gantry-style approach to 3D printing may result in fibers that are not ideally angled for the best reinforcement. To tackle this issue, and to expand the potential of FDM 3D printing as a whole, Arevo Labs has developed a six-axis robotic arm for extruding their materials from just about any angle.
The cost of the system, packaged with its accompanying software, reflects the industrial applications that the technology has. At a price of $150,000, running up to $1 million for larger volumes, this is no consumer or prosumer machine. Then again, consumers and prosumers are less likely to 3D print with carbon nanotubes than the real target markets of Arevo Labs, the aerospace, oil and gas and medical industries.