What In the World is This Metal

[Marcus_Aurelius]

Some time ago a family friend was kind enough to gift me a ton of old marble tools including a good set of marble chisels. The chisels are a carbon steel with some metal inserted for the cutting edge. This edge is the metal in concern. It does not appear to welded in but instead some sort of brazing as evident by the goldish colored material between the body of the chisel and the cutting edge. I do not believe it to be any kind of steel alloy. Here are my observations:

1. The metal will not show oxidization colors when heated up.

2. Will not polish like steel (a darker appearance)

 3. It is incredible hard and will even leave a deep scratch in hardened 1095.

4. The metal is extremely brittle and will shatter if dropped

5. A 80 grit ceramic belt will barely touch the metal

6. The sparks created from the grinder do not extend more then a 1/8 inch from the contact point with the grinder

7. the sparks do not show any 'flares' or 'fireworks'

Unfortunately the cutting edge is to hard to even use against hot steel, I have tried to draw back the hardness but to no success. I do not know what kind of metal this is, maybe a carbide alloy?

Thoughts?

-Mark

[Steve Sells]

All steel is a carbon steel

Steel is by definition an alloy of carbon and iron

have you researched Tungsten Carbide tips?

[Marcus_Aurelius]

I have only done a quick glance on the web, I was planning on looking more at carbide tips later tonight.

my fault on the ‘carbon steel’ it was meant to read “medium to high” carbon steel 

- Mark 

[Frosty]

Tungsten carbide.

Frosty The Lucky.

[SLAG]

Stone carving tools often have tungsten carbide tips in order to cut or powder stone whilst stone sculpting.

These enhanced tools last much longer than their alloy steel counterparts.

They are especially valued for carving granite.

Granite is not really carved off but is powdered away.to make the carving.

Those tools are really expensive. (hence grinding them is not advised).

Check out the website of Sculpture house for their large selection of such tools. Constantine Inc. may still be in business too.

They were the largest dealer of such tools many decades.

SLAG.

[Marcus_Aurelius]

Thanks for all the info, tungsten carbide is some tough stuff

SLAG - I will avoid grinding on them from now on.

Unfortunately I do not have much use for those chisels, I'll clean em up a bit and remove the gunk on them and go from there.

-Mark

[JHCC]

You might consider selling them to a stonecarver and using the proceeds to buy smithing supplies. 

Or take up stonecarving, of course. 

[jkmas]

The carbide chisels that i own were made (and still are) in Barre Vermont.  Troy & Holden is still in business. They sell good quality pneumatic carving hammers and carving chisels. I also have some heavy shanked hand chisels that work very well.  

The carbide tipped chisels are really only necessary for granite carving.  I carve limestone with the steel chisels which hold an edge for a very long time.  Cutting and carving stone and sharpening my brick hammers is what got me interested in blacksmithing.

It's amazing how tough the thin  braze weld is between the carbide and steel.

[Marcus_Aurelius]

Thanks for all the info, I was thinking the same thing about the regarding the braze weld.

Could be a fun hobby to get into sometime in the future

[Kozzy]

Probably carbide because those tend to be lower cost tools...but some of that kind of thing also use Stellite inserts.  Stellite has variations in the mix so can be better optimized for applications than straight carbides.  It tends to be a little less fragile than carbide also so can be better for tools receiving concussive blows.  Color is a dark gray but not quite as dark as most carbide.