The Steel used to make up our billets vary from time to time but should almost always heat treat the same or close to the same way. We use 5160 (spring steel) 203E (low carbon high impact High nickel mild steel alloy) 15N20 (band saw blade material), 52100 (ball bearing steel), nickel 200 is added at times also.
Our production damascus starts out with 13 layers of the above listed steels and then folded 5 times to produce a high contrast 416 layer damascus.
Heat the blade even on both sides till a magnet don’t stick, heat the blade up till it’s the same color all over even, quench in a light weight oil, peanut oil, 10 wt hydraulic oil ect. If you have an oven, take the steel up to 1550 degrees, after blade reaches furnace temperature, allow the blade to soak for at least two minutes at that temperature, then quickly Quench in 10 weight oil, peanut oil, blade tip first, do not swirl blade in oil.
Temper or draw:
Heat oven up to 350 degrees, and then after 1 hour turn off the oven and let the blades cool down to room temperature, draw again if you wish for a double draw. Some folks chose not to draw the steel but its seems to etch more better if you do, or so it does for me.
ETCHING PROCESS - USE EXTREME CAUTION WHEN USING ACID:
Degrease with acetone, mix ferric chloride (brand name Etchant, from radio shack) Mix Ferric with distilled water, one part water two parts acid, or mix 60% ferric chloride and 40% white vinegar. Dip blade in a plastic container containing the acid mixture, let stand for a few minutes and remove to see pattern,( now that is the best part to see the pattern come out on the blade), rinse blade with warm water and put it back in the acid till the desired depth is achieved in the blade, it could take several minutes to get the depth and contrast you want, but on the last dip remove blade from acid and allow the black oxidation to stay on the blade rinse in warm water & rinse in baking soda to neutralize the acid, (Windex will work also) dry quickly with blow dryer, or some other means, to allow the black oxidation to set, and after it is completely dry, spray with wd-40, tri-flow, Break- Free, or clear paint, is what I use to preserve the finish on the steel.