3D printers have overcome and innovated in the past few years, and one of the aspects where we hadn’t seen a considerable leap was in the strength of the final 3D printed object, this strength and material testing consists of several factors, some worth mentioning are:
- Filling pattern or fiber orientation
- Axis of applied force
- Type of applied force (compression, tension, shear stress, bending and torsion)
Developed in the early 1960’s, carbon fiber is a composite material, made from graphite fiber and plastic resin, obtaining a carbon fiber reinforced polymer as a result; carbon fiber is well known for its high resistance, high stiffness and low weight.
Carbon fiber pieces are made from a process that involves several steps, it starts by setting long strands of fibers and then heating them up in a few phases without getting them exposed to oxygen to avoid fibers from burning, here is where carbonization occurs. This results in a fiber made-up of long, tightly inter-locked chains of about 99% carbon atoms. Later, after carbonizing, the fibers are left with a surface that does not allow a good chemical bond with epoxies and other resins. In order to give the fibers better chemical bonding properties, the addition of oxygen atoms to the surface is required; it also gives the surface a coarse finish for better mechanical bonding properties.
Knowing the advantages regarding resistance to weight ratio of carbon fiber pieces, it is obvious why it’s an excellent material, but the process involved in forming/making a final product, comes at a high cost.
AREVO is a technological company focused in 3D printing and robotics; they are pioneers using a six-axis robotic arm for additive manufacturing (3D printing). AREVO in collaboration with Studio west has innovated even further and has showed their capabilities for developing equipment and software, by 3D printing a bicycle frame using carbon fiber.
Bicycles are known to be manufactured with carbon fiber, but the cost varies from $1,000 to around $10,000. By 3D printing a carbon fiber frame, AREVO has estimated that the cost could be around the $300, making the final product more accessible and cheaper to the final user.
This technology also brings the advantage of lower manufacturing times, since it is no longer needed to produce a mold, or to have an artisan/worker to arrange carbon fiber layer by layer. Another advantage of this process is the ability to manufacture complex shapes that would have required to be made as separate pieces and later joined.
Now, 3D printed carbon fiber prototypes and the final carbon fiber product can be made with the same approach, reducing developing and manufacturing times for a new piece or product, and also letting the development and required tests to be performed directly on the prototype.
3D printing has once again innovated and brought an economic alternative to developing high quality, high resistance and low weight 3D printed objects, we will only hope this technology is publicly available soon.
Source: AREVO, CarbonFiberLife, Zoltek