Is carbon migration during long heats a real issue or just a myth?

[Alan]

You’re looking at a glowing billet that’s been in the forge longer than you wanted, and you can’t help but wonder if you’re ruining it. Has carbon migration ever caused problems for you, or is it merely a blacksmithing legend?

 

[forgeandforget]

Spent way too much time worrying about carbon migration! Most times it feels like a big deal. I've had a couple of pieces softer than I wanted, so there might be something to it.

 

[Lorian]

I used to freak out when a piece was in the forge too long. After some experience, I think carbon migration is real, but only if you're not careful.

 

[Tempered3dge]

One time, a billet glowed longer than it should, and the steel felt off.
Maybe it was just me, but now I try to pay attention, even if most stories seem fake.

 

[Dociron]

Carbon migration is real but with knowledge it can be managed.

If your into knife work or tools and are serious about making quality blades you should never forge the edge thinner than 3/32" thick.

If using a gas forge get one that is truly adjustable ( air to gas ratio) so you can get as close to a neutral atmosphere as possible.

If using solid fuel be mindful of staying in the neutral zone of the fire.

Do not over heat your material, stay within proper working parameters.

For those of you who feel it's something that shouldn't be considered seriously, lets think about case hardening or the making of shear steel. Two processes while working the opposite of decarbonization during forging are both based on the migration of carbon.

Remember working with small cross sections of material as we tend to do in the home forge makes de- carboning more of an issue. The thinner the material the quicker the decarbonization.

 

[Alan]

Cool tips about controlling how carbon moves and its role for making good knife blades, especially the thin parts. Love the practical tips on forge atmosphere and temp control. Thanks for sharing this.

 

[FPDoc]

Cool tips about controlling how carbon moves and its role for making good knife blades, especially the thin parts. Love the practical tips on forge atmosphere and temp control. Thanks for sharing this.

Carbon migration is real but with knowledge it can be managed.

If your into knife work or tools and are serious about making quality blades you should never forge the edge thinner than 3/32" thick.

If using a gas forge get one that is truly adjustable ( air to gas ratio) so you can get as close to a neutral atmosphere as possible.

If using solid fuel be mindful of staying in the neutral zone of the fire.

Do not over heat your material, stay within proper working parameters.

For those of you who feel it's something that shouldn't be considered seriously, lets think about case hardening or the making of shear steel. Two processes while working the opposite of decarbonization during forging are both based on the migration of carbon.

Remember working with small cross sections of material as we tend to do in the home forge makes de- carboning more of an issue. The thinner the material the quicker the decarbonization.

Good post.. prob the reason for the basic principle of... "Forge thick, grind thin", which comes right after "Don't try to forge cold iron"... and "Listen to old guys, they know stuff".
It's a new year folks, have a good one.

 

[Alan]

Good post.. prob the reason for the basic principle of... "Forge thick, grind thin", which comes right after "Don't try to forge cold iron"... and "Listen to old guys, they know stuff".
It's a new year folks, have a good one.

Definitely! Those age-old tips are as good as ever. Create the thick, refine the thin, and always take note of the wise voices around you.