Metal filament causes the most wear to nozzles. I am working on a nozzle that will last a life time and keep the the same thermal envelope as the current brass printer nozzles. This is my website if you want to check out more on this nozzle. http://www.dura-gem.com 1 If you sign up to get notified I will let you know when i launch my kickstarter.
To my knowledge carbon fibre filaments cause more wear then the metal composites, but that’s not very important. Why not just go with the hardened steel nozzles by e3d? Hardened steel is the hardest (=> most wear resistant) material you’ll be able to afford, anything beyond that would be crazily expensive. Not only the material cost, but also the machining of materials that are harder then hardened steel is very expensive (or impossible). E3d doesn’t only harden the nozzles, but they also get some chemical treatment to make them more heat-conductive. That’s another mayor point when it comes to nozzles that aren’t made out of brass: brass (and aluminum, copper,…) are very heat conducive, meaning that they give the heat to the outside / filament more efficiently then steel. That’s also, why heat sinks are made out of aluminum. Now aluminum and copper are both VERY soft (in terms of metal) so brass is the best pick. Even if there are exotic alloys that are harder then hardened steel they would cost much more and might not be that heat conducive. Also it’s possible to first machine the nozzles and then harden them, making the drilling etc. much cheaper / possible.
