Note: A lot of stuff surrounding this contribution has been omitted; both articles were copied in one file. If you are interested in the original, the link is: http://www.ald.net/middlemarches/vigil/1997/V_9709.htm
by Lord Mikal Isernfocar called Ironhawk
When the first steel weapons appeared in battle they must have seemed fantastic both to their wielders and to the unfortunates they were used against. Harder and sharper than bronze weapons, steel cut through the leather, horn and bronze armor of those days with an ease that would have seemed "magical" to the average, supersitious fighter of those earlier ages. In addition, steel swords held a highly reflective polish and often rang when they glanced from a solid object. To a bronze wielding fighter, a steel sword must have seemed like a weapon from the gods that 'sang', 'glowed', and 'magically' cut everything in its path. Where did they come from and how were they produced?
There is strong evidence today to show that iron production began in China and India somewhere around 2000 BC. By 1100 BC, the technology had migrated into the Middle East and Egypt but it did not reach the area of Britain until as late as 100 BC. In all areas, the production of early iron was some variation on the following process. Make a pile of fuel. Stack ore on top of it (this might total several layers of fuel and ore). Cover the whole with mud or clay or something to hold in the heat and hold out the air. Vent the top and bottom to create a draft and leave a place for the molten iron to run out. Light it and wait. If you did it right and if your fire is hot enough and if the ore is rich enough (and if and if and if), eventually a puddle of iron will form at the bottom of your pile. This 'puddle iron' is very low in carbon content (and therefore, very soft) and high in impurities. After this puddle solidifies, it is reheated and pounded repeatedly to hammer out the impurities. Another effect of this process is that repeated heating and hammering raises the carbon content of the iron, making it harder and better able to hold an edge. This primitive method of iron making produces what is commonly known today as wrought-iron with caste iron (a high carbon, brittle by-product) and a high slag content as impurities. It is interesting to note that this method is similar to the method used to produce copper from malachite ore and is still used in some poorer regions of the world today.
At first, iron technology had little effect on the cultures it sprang up in. Many early iron utensils are essentially the same as their bronze and copper counterparts. However, the more this material was worked, the more the smiths learned about making it harder. Eventually, three methods of hardening iron into steel came into common usage: watered or pattern-welded steel, wootz, and true damascus.
Watered or pattern-welded steel were the method most common in early Europe, Japan and later, the Phillipines. In a simplified explanation, small soft bars of iron were obtained and forge welded (joined by heating to a temperature just below burning and then hammering the pieces together) over and over until sufficient size and hardness were reached. The repeated folding and welding increased the hardness of the steel by introducing carbon through the repeated heating and hammering. This was a long and tedious process and many pieces were ruined before reaching a finished product since it is very easy to burn steel when it is heated to welding temperature. In fact, the higher the carbon content gets, the easier it is to burn the metal, thus ruining the piece. The subsequent layers of hard and soft metal created by this process produced the characteristic 'watered' pattern seen in articles made of this material. The fewer the welds used, the larger the water pattern. Some Japanese swords have upwards of 36,000 layers and it is very difficult to discern the watering with the naked eye. Obviously, these pieces were able to be reheated and reforged at will and according to how the metal was manipulated during the forging, many different patterns are possible. In the 1950's a gunsmith in England produced a shotgun barrel for Queen Elizabeth's husband which read Prince Phillip, Prince Phillip, Prince Phillip, in spirals all the way down the barrel. This is a very beautiful, functional method of blade production and was the only method available in Europe prior to the Crusades but it was not Damascus.
Wootz also shows a 'watered' pattern on the surface of the steel but for a very different reason. Wootz was produced (mainly in the Indo-China region) by the following method: Wrought iron and charcoal powder were placed in a sealed box, (I assume the box was ceramic) and heated in a furnace until the mixture is reduced to slag and 'buttons' of steel. The buttons were seperated from the slag, remelted and poured into stone molds in the shape of the item desired. As the liquid steel cooled slowly in the mold some structural segregation of the molecules occured creating concentric ring patterns in the steel. After the item reached a solid state but before it cooled completely, it was removed from the mold and hammered into final shape. These pieces could be reheated and reforged if necessary but generally were not. Final work was done by filing, grinding and polishing.
The final method to be discussed here is true Damascus. The most famous and misunderstood of all production methods, damascus steel gained its fame in Europe and later world wide due to encounters with the Crusaders. There are many legends surrounding the famed Damascus steel, all of them dealing with its fantastic flexibility and ability to a razor edge. One such story tells of a meeting between Richard Lion-Heart and Saladin (by the way, they never did meet). As the story goes, Richard, to impress the Muslims, cut though a thick iron bar mounted on a stand with a single blow from his broadsword. Saladin, rather than showing any awe at this feat, threw a silk pillow into the air and sliced it to ribbons with his damascus blade. According to another legend, the common damascus blade was so flexible that a man could take the hilt in one hand and the point in the other and bend the blade in a circle around his body and when released, the blade would spring straight again. So what is different about the production of this steel from that of pattern welded or wootz?
True damascus steel, as made in the vicinity of the city of Damascus, was produced in this manner. Low carbon wrought iron was hammered into very thin sheets. A stack of these sheets was wired together in a tight bundle. A batch of high carbon caste iron was heated until molten. The bundles of low carbon wrought iron were plunged into the vat of high carbon caste iron. The cold wrought iron would 'suck' the molten caste iron into the spaces of the bundle by a process called capillary action. This would partially remelt the wrought iron, 'welding' the bundle together into one solid mass. This mass was forgable for a short time, so it was hammered into rough shape while it was still hot. One major problem with pieces made this way is that they cannot be reheated and reforged like pattern welded and wootz steel can. Due to the caste iron content, when a piece of true damascus is reheated, a blow with a hammer causes it to splatter into numerous pieces, as European smiths found out when they tried to reshape some of the weapons brought home by the Crusaders. Therefore, after the rough shaping as the initial heat cooled, all of the work done on true damascus blades was done by filing, grinding and polishing. As the pieces were shaped by removal of metal, layers were revealed creating the distinctive pattern which creates the confusion in identifying these processes.
Three additional facts are pertinent in discussing blades made by these processes:
First, in true damascus, the cutting edge is actually not a single razor edge but a serrated edge. The 'watering' in these blades is caused by layers of hard and soft (high carbon and low carbon) metal. In sharpening the alternating layers of hard and soft metals created by these processes, the softer layers grind away quicker than the harder layers, leaving a microscopic, toothed edge. This edge slices soft items better than a single edge but does not stand up as well to hitting armor as it has a tendency for the tiny teeth to break off and so the edge dulls quickly.
Second, the iron ore in the vicinity of the city of Damascus has a 7% content of a mineral which was called Wolfram in the Middle Ages. Today we call that mineral Tungsten and it is used to make some of the best metal alloys in the world. In retrospect, it means that the smiths in the vicinity of Damascus unwittingly produced some of the worlds first mass produced composite alloy steels.
Thirdly, true damascus stopped being produced in the 14th century when the Tartar conqueror Timur Leng raided the city of Damascus and took all of the swordsmiths to work for his army. The city never did recover as a metal working center after that.
I would also like to clarify one further point. True damascus production was stopped by the invasion of Timur Leng and wootz continued to be made in India but what happened to Europe? The pattern welded blade went out of favor rapidly in Europe with the invention of the Catalan furnace in the 1300's in Spain. The Catalan furnace was an early blast furnace which increased the carbon content and lowered the impurity content of whole batches of steel by blowing hot furnace gases up through the molten metal. It was the first method used to directly produce large amounts of steel with a uniform carbon content and it made possible for the first time the forging of weapons and armor from one large uniform piece of steel.
Now that you know a little more about the processes, look a little closer at the next damascus sword you pick up. You might be surprised at what you now see.