Someone asked me recently, what is damascus? Simply put damascus steel is what you get when you take two or more types of steel (usually), put them into a forge, bring them up to welding temp (about 2000 - 2100 degrees), pull them out and quickly hammer them together into one solid pice of steel.
Typically you will start with 5 - 10 layers of steel approx one inch wide, 3 inches long and 1/8th" thick.
They will be stacked together in alternate layers. One end of the stack will be welded together and welded to an iron rod. You'll heat it up to forge-welding temp, pull it out, whack it with a hammer (starting at the welded end)
in order to weld all the layers together. Then you will stick it back in the forge to reheat it and repeat it.
After you're sure that you have welded all layers in all places, you will begin to draw the bar out. You will make it thinner and longer. When it is about 7 - 8" long, you grind the top clean, score it in the middle, and bend it in two; clean side to clean side. Then you heat it back up to forge-welding temp, yank it out and whack it with a hammer until the gap is closed and you have one solid piece of steel again. You do that over and over and over and over and over until you have the desired number of layers. Usually that is around 250 layers, though the range is from 50 to about 400. After you have your desired qty of layers, you can grind all sides of the bar clean to see if you have any voids. If you used lots of borax for flux, and hit each hammer blow just right during each forge weld, you won't have any voids. Now go forge to shape and grind a knife blade out of your damascus billet.
After you have ground your knife blade, it is all shiny and looks nothing like damascus. You must etch it in acid to bring out the pattern. Most people use ferric chloride which is a very low grade acid. You decide for yourself and you dilute it to your desired strength. After the acid bath, stop the acid with water & baking soda. Here are some photos of some Robert Eggerling damascus and some links to some info.
Below: some damascus by Pierre Reverdy. His method of making damascus is radically different.
He takes two different types of steel, then laser cuts (or water-jet cuts) the exact same profile of the dragon out of each piece. Then he slides the dragon out of each piece of steel and reverses them; light steel into dark steel background and vice versa. Then he forge-welds them together. Take a look at my next blog post on "Powder Steel Damascus" to see how he gets the recurring pattern.
Below: two different examples of damascus from an unknown maker
Thanks for looking. -Paul