Grind Before or after Heat Treat?; Lessons Learned

If you go to the Sandvik site, they recommend oil quench for their version of AEB-L. http://smt.sandvik.com/en/products/...ening-programs/sandvik-13c26-piece-hardening/ I currently only use high carbon and always grind before HT. trying to grind thin O1 at Rc64-65 is not fun.

You should try some thin A-11/10V at the same hardness. LOL I've found that when I grind thin steel its better to do it in 2"-2.5" sections and then blend them before you move to the next grit. Grinding in the short sections allows me to keep the steel flat against the platen easier. Just what works for me.
 
I agree with Ken. I plate quench with aluminum and have found that due to the nature of aluminum it draws heat rapidly from other heated metals. I believe it makes little or absolutely no difference if the plate is touching the entire blade surface. IMO it would only be micro seconds for the edge to catch up with the cooling occurring with the surfaces that are in direct contact with the plate.
 
If you go to the Sandvik site, they recommend oil quench for their version of AEB-L. http://smt.sandvik.com/en/products/...ening-programs/sandvik-13c26-piece-hardening/.
Scott, I looked a couple of times at that link and didn't seen any reference to oil quench for 13C26. All I saw for quench was: "Quenching: Quench as rapidly as possible. For optimal results 600°C (1110°F) should be reached within 2 minutes or less."
With no mention of how to get there. Shucks, a thin knife blade will almost get below 1110⁰F in <2 minutes just air cooled. Clamped between plates it's there in seconds.
I currently only use high carbon and always grind before HT. trying to grind thin O1 at Rc64-65 is not fun.
Scott: you leave your 01 blades at 64 Rc? That surely would hold an edge, but I would think hard for the average person to sharpen. Since I don't work with 01, 65 Rc might be normal for all I know. Comments please.

Ken H>
 
I made some test mules of O1 and 1.2519(O7) and tempered at 275F. these are thin kitchen paring/utility knives with edge angles of 5 to 10 dps. Rc tests came out at Rc64-65. object was how thin I could make the edge and have it last, have done ok so far but I use the knives only for fruit, veg, and boneless protein on a good cutting board. O1 is an old oil hardened steel that is usually tempered to Rc61-63.
sorry on the link, try here at their hardening overview http://smt.sandvik.com/en/products/...teel/hardening-guide/the-hardening-procedure/ "When the blade has been soaked in the furnace for the time specified above, it is removed and immediately quenched, preferably in oil intended for quenching."
 
Scott, you're right, there is a place on where Sandvik says "oil quench". Talking with John Foster, a Sandvik technical engineer who indicates plate quench is just fine, and perhaps better than oil quench because the plates help prevent warping.
 
If you want to try oil quenching higher alloys, D2 and A2 are also oil quenched often, use plates after about 7 seconds in the oil. I've read from a few tech articles that faster quenches in higher alloy steels can reduce retained austenite. I don't think in a major way, like cryo will, but in a small way.
 
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