What temperature to normalize O-1?

Kevin, Mete, et al.,

I'm not metallurgist and I'm new to this knifemaking stuff, so please forgive my dumb questions. (I've been reading you guys for months now and trying to get a handle on it all, but I'm afraid it hasn't all soaked in!) The thing that has me confused about this thread is the presence of alloying elements like manganese, chromium and tungsten in O1. My simplistic understanding is that the alloying elements inhibit carbon's ability to go into and out of solution in iron, which is why we can afford to take longer to get below the nose of the TTT curve in oil-hardening steels like O1: the carbon can't scamper out of solution as fast when the steel begins to cool, so we have more time to "freeze" it in place during the quench. It's also why a soak is recommended for deeper hardening steels like O1: because it takes some time for the carbon to get into solution once you get to the austenitizing temperature. (Again, this is just my layman's understanding. It may not be right!)

Assuming that's somewhere close to correct, how do the alloying elements play into normalizing? If part of the point of normalizing is to dissolve carbon into solution so that it'll reform as more evenly distributed carbides when we cool it, and if it takes a while for those carbides to dissolve, why don't we need to soak when normalizing?
 
All diffusional processes are dependant upon time and temperature, it is often put as "time=temperature", but they are hardly equal when one considers how much more powerful temperature is than time. If one is not concerned about grain growth or putting too many things into solution, you can reduce time to seconds by going high enough in temperature. This is why industry recommends the 1600F or better, and is also why I use it on the first heat. At this temperature not soak is necessary to get the same results you would get over much more time at 1475F. Get that steel hot enough to get everything diffusing within it and you will evenly and widely disperse things and have a very level playing field to begin your subsequent refining heats. As I said, forget about grain growth on the first heat as long as you can grow the grains to all the same size, then the lower heats will be much more effective in even refinement without the danger of uneven coarsening.
 
Thanks, Kevin. That makes sense; I just didn't realize an extra 125 degrees would make such a big difference.
 
To this up:

1. slowly heat to 1600F, hold for 10 min
cool in open air to 500F

2. put back into furnace preheated to 1500F
cool in open air to 500F

3. put back into furnace preheated to 1450F
cool to room temperature in open air.

Right?
 
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