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Is it possible to electroplate carbon fiber? Answered

Hi, I'm into knifemaking. There are some carbon fiber knives on the market, but they all have very poor edge retention. (because the edge is made of carbon fiber as well)
I was wondering if it would be possible to add a thick metal coating of a hard metal to a carbon structural center, as to coat the blade in a thin layer of metal. This metal would then be serving as the cutting edge, hopefully with better edge retention. 

Is this at all possible?
What types of metal could be used?

Thanks in advance!


Yes and no. You can plate a layer of metal over the carbon. i have done this to plate leaves off trees with copper. First you need to make them conductive so you spread glue on them and dust graphite over them to give a conductive surface.

HOWEVER the adhesion of the metal layer to the graphite isn't very strong.

The carbon already being conductive, would this help get a reasonably strong adhesion?

Are there any hard metals you would recommend for this?

No graphite and carbon are the same thing. the adhesion, at least in my experience, is poor. It is good enough for jewellery but I wouldn't rely on it for much mechanical strength.

Your also NOT going to be able to plate on a metal that will take an edge, bronze maybe but I have no experience of this. Normal plating is none ferrous metals.

The only thing you can do is to sandwich a thin metal strip into the blade.
Basically you make a lot of holes into the metal strip and add even layers on both sides to form your actual knife.
But the basic problem will persist that carbon fibre is only light but really usable for cutting.
A huge deal depends on the resin used as this gives the actual hardness on the edge.
The fibres need to be along the cutting edge to prevent them from splitting but that can't be done in a multi layer way where the fibres need to cross each other for strenght.
Some industrial carbon sheets use aligned fibres that all go in one direction, made from quite short fibres, maybe it is worth trying them for a knife but the stuff costs an arm and a leg...

+1 for the hybrid idea, carbon steel cutting edge with dovetails/keys that extend into the carbon fibre main blade.

However, dissimilar materials with different flex factors might cause edge shear/separation.

Not really as we are talking very thin here, like a razor blade.
And in normal knifes is not really much flex, so if the carbon fibre is a bit thicker it won't matter as long as the transition from metal to fibre is smooth.
I tried similar in the days but used these sharp wall scraper blades.
Only problem was the thickness and the fact that they were sharpened from only one side, so the "back" is flat.
Steel for feeler gauges can be ordered in sheets and cut to the prefered shape, this way you play with the thickness and still have reasonably good steel for the edge.