I get a lot of questions regarding damascus steel and how do the patterns form in it.
Although the principle is rather simple, I've noticed that it is extremely hard to try
to explain it in words. For that reason I've prepared here a description about it. In addition
I want to emphasize that this is not the only way to make damascus steel but a glimpse of how I
do it. That being said, this is not ment to be a tutorial and I don't recommend anyone to use
it as one and I don't take any responsibility of it.
In this example I use 0,8% plain carbon steel which I signify C0,8% and nickel steel 15N20.
These steels have rather identical working and heat treating characteristics.
In practice only difference between the two is the 2% nickel content in 15N20 steel
which among other things reduces corrosion in etching. Plain carbon steel (C0,8%) corrodes
more quickly revealing the layered structure.
I start by grinding the steel surfaces clean from rust and other foreign matter.
After this I cut slabs of equal length which I pile in such way that every other slab is
plain carbon steel (C0,8%) and every other is nickel steel (15N20).
After that I MIG-weld slabs together forming a billet and I weld a handle to it so that it
is easier to handle. There are now 10 layers in the example billet. (PICTURE 1)
Next it's time to light fire to the forge. First I heat the billet to cherry red temperature
and take the billet out of the forge to tighten those slabs more closely together with a few
hammer blows. After that I sprikle some borax over the billet. (PICTURE 2).
Borax is used in forgewelding as a flux. It covers the billet and seals it from oxygen
thus preventing scale from forming, which would interfere the welding.
Next the billet is heated in to yellow / starting white heat. When this temperature is reached
billet is kept in the fire for a while longer, allowing temperature to equalize.
Now I bring the billet to the anvil and quickly but lightly hammer the weld shut starting
at the center proceeding outwards. When the weld is hammered shut liquified hot borax and
scale it has dissolved fly out of the seams (PICTURE 3).
It is necessary to work very quickly because as soon as billet is taken out of forge
it's temperature starts to fall rapidly and one has only few seconds to make the weld depending
of the size of the billet. If billet cools down too much slabs wont weld properly and only option
is to cover the billet with borax and heat it again.