Filaments under the microscope!
https://www.youtube.com/watch?v=vVquEtmekDw
Does anyone manufacture a tungsten-carbide nozzle?
These guys weren’t successful with their campaign, but I’ve seen some around. It’s really not necessary. The hardened options are all you need.
https://www.kickstarter.com/projects/dddmaterial/3d-printer-tungsten-premium-nozzle-0
@Taylor_Landry yeah - I had a quick look at their nozzle too.
They are using a softer tungsten alloy - not tungsten-carbide - but in any case I don’t think that something extremely hard like tungsten-carbide is worth the extra expense.
So I think that tungsten-carbide is probably overkill - very few things will scratch it except diamond and quartzite. The main problem is that it is very difficult, and therefore very expensive, to mill the 0.4 mm hole. I think the softer tungsten alloys are not much easier that tungsten-carbide either.
In terms of the ability to machine an accurate hole, combined with an acceptable surface hardness - my guess is that case-hardened stainless-steel is the best option. It’s much easier to accurately form the nozzle from ordinary stainless steel, then use a case-hardening technology to protect the surface from scratching.
The hardness of case-hardened stainless steel isn’t as high as tungsten-carbide, but it is still very hard - certainly hard enough for 3d printing bronze, carbon-fibre, and ordinary stainless steel filaments.
After a bit of searching I found this article that makes a takes a detailed look at wear and tear on case-hardened stainless-steel nozzles:
http://e3d-online.com/is-carbon-killing-your-nozzle
I think for the foreseeable future, tungsten-carbide is out and case-hardened stainless-steel is the way to go for abrasive filaments.