[Jared Lambert]

I recently have seen a couple of knife or sword makers that use crucible steel which has a unique look to it however I don't know a lot about it. For instance what effect does adding glass do to the metal? Also what makes crucible steel better than average steel? Any answers would be much appreciated.

[Richard Furrer]

Hello Jared,
In my work I make and use crucible steel and wootz and a few other steels because it places me that much further down the path of a hand made product. It allows freedom to take the raw materials from beginning to end and continues a tradition which stretches back in time. Better is a difficult term and one I prefer not to use.

The glass is a flux and helps with the melting of the metal in the crucible by removing oxides. Depending upon the chemistry, time and temp of the melt some of the silicon may be incorporated into the steel.

Not all crucible steel is the same...just like not all pattern-welded steel is the same.....chemistry varies such as carbon,major alloy elements and impurities .... as well as other things.

Depending upon what is meant by the maker..i.e. what his/her "crucible steel" is would be the answer to your second question on what makes it better. In short..there is no real answer to that question...or rather that answer may be "that depends".


Historically speaking when all other materials are bloomery steel with the inherent impurities involved in that process and you have the a crucible steel blade which has less inclusions and slag due to its technology of manufacture one may make the case that the crucible steel blade is "better" in some ways.
When I was in India I saw first hand hardness tests done on bloomery and crucible steel blades...on average the crucible steel blades were harder. Proof is in the video section of my website as I have video of the testing.
http://www.doorcountyforgeworks.com/Videos.html
near the bottom.

However, as such things were a craft then and are a craft now there is variation from one to the next and as with historical pieces and modern hand made blades much depends upon the craftsperson.
I have been making steel for about 2 decades now and have a good handle on the various pitfalls and promises and I still struggle with the myth vs my experiences.

Ric

[Jared Lambert]

Richard thank you for the info! I never thought of glass as a catalyst but i know silicon is added to metal so that makes since ill be sure to check out that link>