3D printing carbon fiber reinforced hybrid resin.
I have been developing a new material I called NEFCAR ( Novolac Epoxy Filament with CARbon ) that has been specifically designed to my requirements. Tests have been successfully ongoing for several weeks now.
The filament is a blend of Epoxy Phenol Novolac ( EPN ) and poly-DL-lactide resin developed in Japan.
The resin acts as a latent hardener and combines to EPN at high temperature.
The biggest challenge was to find the right printing bed and nozzle temperature that would allow the material to cool down slowly enough to allow the nano carbon fibers to align along each other and create continuous filaments bonded by the hybrid resin.
This is pretty much a first time in the world and I am very happy with the material characteristics. The part is about 30% lighter than with PYCABS and 75% stiffer. The high level of nano carbon fibers reinforcement makes the part incredibly easy to glue with epoxy resins.
After lots of tweaking and printing head modifications, I can now print 3D honeycomb reinforced epoxy/ carbon fiber parts.
I have reached a point where I can say that this is the most incredible material I have ever been able to work with.
Here is a video of a part printing as you can see, the head travel speed is quite fast:
Here are a couple of pictures of the part finished. The honeycomb filling is almost visible through the 0.2 mm carbon fiber layer.
Note the hinge recess and control horn already included in the printing from the CAD stage. Zero fiddling with door geometry on this part!
Here is the back of the part. the carbon fiber nature of the material is immediately evident when you get the part in your hands.
This is similar to what the Harvard University have managed to achieve but with a different technique. They use an Epoxy printing ink on a 100% custom printer where I use a thermofused hybrid epoxy/ polylactic resin/ nano fiber mix that is dispensed through a 75% modified Stratasys printer.
Last edited by olnico; 11-01-2014 at 02:06 PM.