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Sorry - couldn't resist. Kevin, you know how much I respect your advice and I think you know I'm not knocking it - but it already had my simple undergrad head spinning long before this.
What I'm reading here - from all of our KD expertise - is that black may not be enough for a whole lot of reasons. Having said that, the ability to hold it in my bare hand without screaming in pain may not be quite required either - especially with some steels like 1084. I have read this thread over and over. I'm thinking if I can hold the blade without morphine, it's good for the next cycle. The difference between too hot to handle with bare hands (maybe 300F?) and room temperature can be an hour. I think the advice here will help me save
some time, but I'm trying not to read too much into it. ALL the advice is much appreciated.
The problem with simple answers is that they always come with a whole line of “excepts”, i.e. “just do it like this… except when you are using this steel, and except when you want to machine it, or except when you want to lamellar anneal it, but not if it is a hypereutectoid etc… etc….”
That being said, the simpler answer is that if you are just looking to refine grain wait until the magnet sticks again and then go back to the heat, if you are looking to homogenize everything, including any residual strain energy that could cause warping the cool until you can hold it in your hands. And while you are holding it in your hands have a look, as Tai advises, to see if any warping did occur, if so, fix it and normalize again.
Sorry about that, I just refuse to give “just do this and don’t ask why” answers as I feel they limit you more than help you. The reason so many flock to knifemaking is the challenge of accomplishing something that is not simple or easy, otherwise, well, it would not be much of an accomplishment. When I was six mastering tic tac toe was great but now I prefer the rewards of more substantial challenges, so the true complexity of this craft still excites me.
Now here is another complication that I didn’t add, but some others have mentioned, and it does complicate things to be sure. If you quench during normalizing, which would mean you couldn’t actually call it normalizing anymore, you must then be certain to go all the way to hand cold. By quenching you will be austenitic all the way down to warm. If you quench to just below black and then reheat you are just reheating the same austenite again, even with 10XX series. Think about it, the whole point of quenching is to avoid making pearlite, if you don’t make pearlite all you have is austenite until another phase is made, so you can wait on the possibility of upper bainite taking up the slack, or you can cool all the way to room temp and let martensite do the job. So the quench method needs to be all in or all out, otherwise you are in limbo. Not that there is anything wrong with using a quench cycle for faster refinement, I often use it to keep carbides where I want them and really get on the grain size, but it does complicate things.