I would like to know more about Damascus steel and have found two very different explanations for what it was. The first is that it was a form of pattern welding. The other is that it was a crucible steel. What actually was it?
Truthfully, we are still trying to understand the process of Damascus steel! We still don't know how the ancients did it.
It's widely believed to be the process of tempering steel to make it stronger, studies have shown Damascus steel to contains nano-fibres which greatly increased it's strength and durability compared to other metals of the time.
However we've only recently been able to duplicate the steel with modern techniques, as said we don't know how the it was actually done. And only in modern times have we had the technology to see and know that nano-fibres were the reason that made it stronger.
It was both!
There's two types of steel called Damascus steel, you can't see a difference with your naked eye.
The first (pattern welding) is a folded steel, with two initial layers of high and low carbon steel. This is not actually remarkable other than its appearance compared to other steels of the time.
The second, which the legends come from (its not up to that level, but the stuff is unique), is a crucible steel. With and low carbon steel that contain one of vanadium, molybdenum or a third I forget. Very very small amounts of these elements are needed, around 100 parts per million, the technique was likely lost because the iron mine the crucible version was being made of was shut down, and it was actually budget concerns that led the metallurgist who discovered this to use an ore with appropriate impurities, he knew they were in the wootz damascus steel but thought them too trace to be significant.
Source: The key role of impurities in ancient damascus steel blades J. D. Verhoeven, A. H. Pendray, W. E. Dauksch
http://www.tms.org/pubs/journals/JOM/9809/Verhoeven-9809.html?ref=Klasistanbul.Com
Like u/ Perdi said we don't know the secrets of old Damascus steel but the modern version essentially entails gathering different types of metals and "mixing" them together by folding the steel over itself many times during the process of making the steel. This makes really cool patterns in the steel like this http://www.mountainhollow.net/graphics/hunter-raindrop-damascus.jpg
I'd recommend that you view some videos on YouTube of Damascus steel being made to get a better idea of what I'm saying
