Working D2 Steel

[jake donovan]

Hey All, started working with D2 steel recently, followed a HT/Tempering formula I found. Tempered twice at 500 degrees....tried to bend the blade, but it snapped at about 20 degrees. Blade came out so hard it's a pain to grind at all! I guess it's still too hard. Would a third temper help? Forgot to tell you the blade is 3/16 thick.

 

[A.McPherson]

Increase your temp to soften the blade. Since it's broken already, break it into smaller pieces and do some testing at different temps.

That'll get you some good results where you can figure out what temps you want to use to get to your desired hardness.

Remember, flexibility is a function of geometry, not hardness (in a general sense at least).
Thin is flexible, thick is not.

 

[AVigil]

A 50 grit ceramic belt should handle it

 

[Larrin]

It’s hard to grind because it’s wear resistant. It snapped because you had a thick blade and low toughness steel. Neither of those things means it was heat treated incorrectly. Of course you would know for sure with a hardness test.

 

[Stacy E. Apelt - Bladesmith]

Out of curiosity, why were you bending the blade.

 

[Natlek]

Out of curiosity, why were you bending the blade.

Because it is only way to break it

 

[TheEdge01]

I believe D2 also needs to be cryogenically treated as well.

 

[JTknives]

I believe D2 also needs to be cryogenically treated as well.

It doesn’t have to be but if you don’t then you do the high temper to reduce retained austenite. Also D2 does not need cryo (-320°) it needs sub zero (-100°) if doing the 400° temper. You can use cryo if you got it, does not hurt.

 

[Stacy E. Apelt - Bladesmith]

D2 with cryo and a low range temper can be VERY hard and tough.

Austenitized at 1850-1875F
air cool or plate cool to room temp
cryo (or dry ice bath if no dewar)
temper at 350F/400F for one hour, twice. Rc 62/60.