The term damascus refers to the moiré cloth woven in the city of Damascus, not to the swords that were forged there.
Damascus is a method of refining iron by successive hammering, bending and stretching. These operations aim to eliminate impurities from the metal. The result is a composite material with alternating layers of more or less homogeneous iron, steel or nickel.
This heterogeneous texture induces quite exceptional mechanical qualities, because damascus is only partially tempered (neither iron nor nickel are tempered), the metal is thus not very brittle and resists fracture because it diffracts shock waves.
There are several techniques for forging damascus:
- The Western or Merovingian technique,
It was used by Merovingian smiths; it was in fact a form of wrought iron which was lost, in an unexplained way, towards the end of the 10th century.
- The oriental damascus or fusion damascus is the damascus par excellence;
The wootz is the equivalent for the blacksmith of the philosopher's stone, but in spite of a ceaseless alchemical quest, it seems that nobody has been able to recreate the very complex process of its elaboration.
- Japanese damascus is the damascus we find today.
It is forged by hammering and stretching.
The several thousand layers of sword blades have gradually given way to a smaller number of layers (a few hundred). Indeed, beyond that, the texture is too dense, and the revelation by acid does not give satisfactory aesthetic results.
In addition to the undeniable mechanical qualities of Damascus blades, their aesthetic character should be emphasized,
The composite quality of the material has innumerable anamorphic potentialities which depend on both the bending and stretching, and the deep work (e.g. carving) of the metal.
If the damask piece has the desired shape, it can be dipped in acid which blackens only the carbon and thus reveals the structure of the metal.
Stainless damascus, however, with a high carbon content, is made from steel produced by powder technology (very fine grain, wire that holds), because the intrinsic mechanical quality of the metal allows for a very hard temper
(up to 63-4 Rockwell) after cryogenics.
Powder metallurgy
In powder metallurgy, the molten ore is passed through a vacuum chamber where it is sprayed with argon gas. The gas droplets attach the molecules. The ore is then transformed into powder.
Depending on the quality of steel desired, the different powders are then mixed, heated in a vacuum isostatic furnace and compressed under high pressure (2000 bars).
The steel thus obtained is almost completely free of pores, which allows it to be used in high-tech industries such as aerospace.
In cutlery, powder metallurgy steels are the material of choice for the manufacture of high carbon stainless damascus. Different patterns with remarkable aesthetic qualities are obtained depending on the successive bending and stretching during the forging of the damascus.
This article deals with damascus blades in general and not with those sold on this site.
Damascus steel blades and their manufacturing techniques in the world
