Chromium coated titanium knife?

A

Avalon11

Joined
Dec 26, 2018
Messages
4
Hello. I want to make fixed titanium alloy knife for travel and all place carrying. Titanium despite not being popular and not having best sharpness has serious lower weight advantage up to 40% and as well corrosion resistance over steel. I plan to make not small knives with 7 and 8,5cm long blades and ergonomic handles so that a lot weight addition. Titanium is not as hard as hardened steel, but still harder than ordinary steel. I came up with an idea to counteract this Ti problem by hard chrome coating since chrome is very hard having even 8,5 Mohs scale hardness. Problem with that could be only that chrome could peel off titanium with bad quality electroplating. I would want to deposit strong and thick chrome layer on knife edge to sharpen it and hold well against activity such as cutting wood, branches. I plan to use grade 5 titanium alloy which has 6% aluminum, 4% vanadium and trace of iron, as well oxygen. From what I read surface preparation, grease, dirt and oxide removal is very important step for good chrome bond. What kind of salt would best to use for electroplating? I seen that professional chromers deposit on steel copper layer and only then chrome, would that help titanium?
 
Well I considered even making carbon fiber knife with embedded steel razor but titanium solid body seem like more durable option.
 
Avalon11 said:
Well I considered even making carbon fiber knife with embedded steel razor but titanium solid body seem like more durable option.
Click to expand...
What they do is they take a titanium, chisel ground blade and cover the unground side of the blade with a layer of carbide coating, giving the knife a hard, carbide edge when you sharpen it.

I’m not an expert, It’s a bit early now, but I’m sure the Americans can tell you much more about it when they wake up. :D
 
If you want a titanium blade with a chrome edge, the best way might be to have a laminated blade with titanium on the sides and a chrome plate forge welded into the middle, making up the edge.

I’ve never heard of anyone putting pure chrome into a knife blade like that though, there might be a good reason why people generally don’t. Concerning toxicity for an example.
 
Is chrome really that toxic? Chrome parts are used almost everywhere, interiors, bathrooms and so on. If steel is chromed why not chrome titanium as well?
 
It 'can' be done, but the process is very delicate, and very reliant on removing the Titanium oxide layer first to get a really good bond. Companies actually specialize in it: (and have 'proprietary processes' to do it)

oh, and the toxicity IS a concern, especially depending on which chrome plating method you use, hex- vs tri-chrome (read this) https://en.wikipedia.org/wiki/Chrome_plating
TL/DR hexavelent chrome plating is outlawed in europe, and heavily regulated elsewhere because of this

This is one company that will do it: https://www.uschrome.com/chromium-on-titanium

let us know which path you go with and how it works out? : )
 
Mecha Mecha

Paging the king of Ti.
Avalon11 said:
Titanium despite not being popular and not having best sharpness has serious lower weight advantage up to 40% and as well corrosion resistance over steel. I plan to make not small knives with 7 and 8,5cm long blades and ergonomic handles so that a lot weight addition.
Click to expand...

I’m not sure I understand the logic here. Converting this into 'Murican, that comes out to blades of roughly 2.75-3.3". That's relatively small, and in small knives, is there really enough weight difference to be worth the bother to use Ti? I can certainly understand if it’s for a machete or sword, but on smaller knives how much weight savings do you get? I mean I see knives in that size range pretty frequently that weigh about 2oz or 3oz in steel (ESEE Izula and Becker BK11 checked for reference). So for all the bother of using Ti you save about an ounce of weight on a knife that's already so light you'll barely feel it?
 
PS - you might get a better result if you just go for a TiN or TiCN coating, since your base material is Titanium. I think getting a Nitrogen atmosphere to anneal your finished Ti blade inside of, might be overall easier.
 
19-3ben said:
Mecha Mecha

Paging the king of Ti.
Click to expand...


Did someone say titanium?

giphy.gif



That's a good patent link D dirc posted, useful for the OP's idea.

Seems like a cool idea to me. Tungsten carbide on one side works well as mentioned, I found that it works on plain 6al4v or softer ti alloy, but not very well at all on hardened ti alloy. Chrome on only one side would probably be better than a fully chromed knife.

The problem with removing the oxide layer is that a new oxide layer forms almost instantly, unless it's in an oxygen-free environment, argon for high temperatures.

In a metallurgy class about identifying different metals and alloys, the instructor handed the students a mystery piece of metal, super shiny and almost weightless. It took a minute to figure it out - it was chrome-plated aluminum!

There can be a good reason for a super light knife. I sent a small, thin fixed blade to a friend, who said it turned out to be a perfect sgain dubh, which is meant for "sock carry." :D




Y3ED02y.mp4
 
Last edited:
lol, nice gif... but have you ever done Chrome or TiCN or TiN on your titanium blades? I'm guessing you have not invested in a nitrogen chamber setup yet, but it sounds like it would be awesome
 
Avalon11 said:
It would be faster if somebody just told. Nobody here has experience chroming blades?
Click to expand...
I make/have several hard chrome blade with 52100 steel .Whatever you do you will have titanium on edge when you sharpen your blade as I have 52100 steel on edge on my hard chrome knife , but it looks very cool ...and hard to make scratch :D
 
dirc said:
lol, nice gif... but have you ever done Chrome or TiCN or TiN on your titanium blades? I'm guessing you have not invested in a nitrogen chamber setup yet, but it sounds like it would be awesome
Click to expand...

Sure haven't, can't think of a good reason for it.
 
Very bad idea. Hard chrome plating a knife edge made of a much softer substrate won't work. Pressure will simply crumble the chrome edge and deform the titanium.
The plating would not be thick enough to sharpen. You would simply wear it away.
It sounds like you want to make a knife that you can carry on an airplane. What you are proposing will not allow that, and it simply won't work.
 
so... essentially, the best idea to achieve what he's after would be to do a TiN or TiCN treatment?? It's used to great effect on the kershaw nura, cryo, and many others with great reports and results on cheap 8cr13mov steel... but nothing really on standard 6-Ti alloy (at least in a knife context)
 
Last edited:
dirc said:
so... essentially, the best idea to achieve what he's after would be to do a TiN or TiCN treatment?? It's used to great effect on the kershaw nura, cryo, and many others with great reports and results on cheap 8cr13mov steel... but nothing really on standard 6-Ti alloy (at least in a knife context)
Click to expand...


I think the best way to make a knife like he describes is to forget about chrome and just do the tungsten carbide on one side thing. It would be fine for basic knife stuff, like cutting wood and branches and such.
 
You must log in or register to reply here.
Back
Top