3D printing has long been heralded as the next frontier in on-demand manufacturing. While the term “printing” is a bit of a misnomer, the machines extrude filaments of various substances into nearly any shape imaginable. The technology has wide-ranging applications in the fabrication and manufacturing space, and allows for a level of granular control and automation never before seen in commercial manufacturing.
Most 3D printers use a plastic-based filament material like PLA, Nylon or ABS. The designer pre-programs the printer with a design schematic, which is then spit out by the device, layer by layer. But as technology inevitably does, the process has evolved to include more exotic materials for advanced applications. Today’s 3D printers can even create commercial-grade steel or carbon fiber parts, which have potentially game-changing uses in everything from aerospace to robotics to consumer electronics.
Markforged is the leader of the carbon fiber printing pack
The best-known company leading the charge of this new generation of 3D printing is Massachusetts-based Markforged. Its first desktop carbon fiber 3D printer, the Mark One, can produce 3D printed carbon fiber parts with a much higher strength-to-weight ratio than aluminum, and claims it can do it up to 50 times faster and 20 times cheaper than conventional methods. The second iteration, the Mark Two, comes with a built-in touch screen, offers even faster printing and the ability to reinforce features a fraction of the size as the previous model.
Markforged printers use two separate print heads to create parts, one that extrudes a nylon filament while the other reinforces it with various composite materials, including carbon fiber. The process creates parts that are considerably cheaper and more accurate than traditional metal machining methods. The high level of customizability enables the printer to create fully functional parts, instead of just stand-in prototypes to be manually machined from metal later on. This cuts down on the design time and dramatically reduces production costs.
Carbon fiber is prized in certain industries for its super high strength-to-weight ratio, making it ideally suited for projects where light weight and strength are paramount (think airplanes and really fast cars). It’s already being used in airplane manufacturing. The Airbus A350 XWB is made up of more than 50% carbon-fiber reinforced polymer, and carbon-fiber reinforced parts are finding their ways into the manufacturing of high-end performance vehicles. However, as the technology improves and the price of materials drops, manufacturers are seeking to implement carbon-fiber components into cars you might more commonly see on the road, like the BMW i3, which uses a carbon fiber reinforced chassis. Materials reinforced with carbon fiber can also be found in everything from bicycles to tennis racquets to surfboards.
Most carbon fiber is created involving a multi-stage heating process of a polymer called polyacrylonitrile, or PAN for short. The heating strips the polymer entirely of its non-carbon atoms, leaving behind only the carbon. The resulting material can either be wound up in spools or combined with another polymer to weave sheets of carbon fiber cloth, which can then be molded to the desired shape and size before being cured by heat or air.
Commercial Grade Manufacturing From a Desktop-sized Printer
Before companies like Markforged made the technology available in a compact size with a price tag of several thousand dollars, previous methods involved massive machines costing tens of millions of dollars. This expensive, labor-intensive process ensured only the biggest and most well-moneyed manufacturers had the resources to reinforce components with carbon fiber. The ability to 3D print carbon-fiber parts drops the amount of manual labor required to almost nothing, and enables small batch or even one-off production runs for manufacturers of just about any size or budget.
A number of 3D printer companies offer the ability to create nylon-carbon fiber parts using a combination of “chopped” carbon fiber and thermoplastic, which can then be extruded for production. These parts are considerably stronger than non-carbon fiber reinforced counterparts, but since the carbon fiber is incorporated into the part spread out in many small pieces, it lacks the full strength and durability of which carbon fiber is capable.
Markforged is one of the only 3D printers that uses a method called continuous filament fabrication (CFF), which continually incorporates strands of fiber filament into the print during the manufacturing process. This uniform application of whole carbon fibers produces a resulting material that is much tougher than chopped carbon fiber reinforcement. Its desktop series, which promises industrial-level quality from a machine that can fit on your desk, offers carbon fiber-reinforced nylon prints that are 20% stronger and 40% stiffer than ABS plastic.
Carbon-fiber printing has the potential to forever change how industrial manufacturing gets done. Any new technological advance inevitably has a few hiccups and doubters along the way, but companies like Markforged offer a unique and bleeding-edge take on the manufacturing process that could wind up saving countless hours of labor and untold millions on the cost of creating parts. Some of the biggest industries in the world are looking at carbon fiber reinforced materials for their products, and there’s good reason to believe we will see this trend line continue as the technology improves even further.