Quote Originally Posted by gregg71 View Post
... How warm the oil would be?...
Your normalizing process should have refined the grain in your bars/blades. Thermal cycling is basically the same process, as I understand it, but you are quenching into oil from 800C rather than waiting for the blade to cool to room temperature. What you want is the carbon to go into solution at above the critical temperature and back below the critical temperature where it will form grains at a smaller size. Repeating this cycle will reduce the grain structure to finer than you started.

I've done this in all range of oil temperatures. Warmed oil will not help or hurt the cycling process but may have more an influence at the final quench to hardness.