HOW TO MAKE A DAMASCUS BLADE，The Mystery of Damascus Blades（附文部分），原载于Scientific American2001年1月号
【楼陀罗案】本文是The Mystery of Damascus Blades的附文部分。正文部分见：http://www.douban.com/note/102227108/
【HOW TO MAKE A DAMASCUS BLADE】
Master bladesmith Alfred H.Pendray demonstrates the technique in his smithy near Gainesville,Fla.
1.Assemble the ingredients to load into the crucible,including high-purity iron, Sorel iron, charcoal, glass chips and green leaves.The quantity of carbon and impurity elements that end up in the ingot is controlled by the proportions of iron, Sorel iron and charcoal added to the mix.
2.Heat the crucible. During this process, the glass melts, forming a slag that protects the ingot from oxidizing. The leaves generate hydrogen,which is known to accelerate carburization of iron. The carbon content of the iron is raised to 1.5 percent,a good proportion for forming the hard iron carbide particles whose accretion into bands gives Damascus blades their characteristic wavy surface pattern. The leaves and glass can be left out, but ingots made without them are more prone to cracking during hammering.
3.When the crucible has cooled, remove the ingot, which bears a resemblance to the wootz cakes used by the ancients.
4.Heat the ingot to a precise temperature. Pendray is using a gas-fired furnace with the propane-to-air ratio adjusted to minimize the formation of oxide scale during forging. Typically, a surface oxide layer of about half a millimeter in thickness forms, and the final grinding operation must be sufficient to remove it.
5.Forge the ingot (deform it slightly with hammer blows while it is still hot). When the ingot gets too cold to deform without cracking, heat it up and forge again.Four separate stages of the ingot are shown here; each stage is the result of several cycles of heating and forging. A total of about 50 cycles may be needed to bang out the blade shape from the ingot—a highly labor-intensive process.Pendray uses a modern air hammer. A handheld hammer works, too, but it takes longer.
6.Cut the blade to final shape andhand-forge to add finer details.
7.Remove the excess steel and the decarburized surface metal. Pendray is using an electric belt grinder for this step.
8.Cut grooves and drill holes into the surface of the blade to create Mohammed’s ladder and rose patterns, if desired. Forge the blade flat again and polish the surface to give the blade its near final form.
9.Etch blade surface with an acid to bring out the pattern; the softer steel darkens, and the harder steel appears as brighter lines.
ALL PHOTOGRAPHS BY WILLIAM ROSENTHAL
【HOW TO MAKE A DAMASCUS BLADE】
Master bladesmith Alfred H.Pendray demonstrates the technique in his smithy near Gainesville,Fla.
 |
1.Assemble the ingredients to load into the crucible,including high-purity iron, Sorel iron, charcoal, glass chips and green leaves.The quantity of carbon and impurity elements that end up in the ingot is controlled by the proportions of iron, Sorel iron and charcoal added to the mix.
 |
2.Heat the crucible. During this process, the glass melts, forming a slag that protects the ingot from oxidizing. The leaves generate hydrogen,which is known to accelerate carburization of iron. The carbon content of the iron is raised to 1.5 percent,a good proportion for forming the hard iron carbide particles whose accretion into bands gives Damascus blades their characteristic wavy surface pattern. The leaves and glass can be left out, but ingots made without them are more prone to cracking during hammering.
 |
3.When the crucible has cooled, remove the ingot, which bears a resemblance to the wootz cakes used by the ancients.
 |
4.Heat the ingot to a precise temperature. Pendray is using a gas-fired furnace with the propane-to-air ratio adjusted to minimize the formation of oxide scale during forging. Typically, a surface oxide layer of about half a millimeter in thickness forms, and the final grinding operation must be sufficient to remove it.
 |
5.Forge the ingot (deform it slightly with hammer blows while it is still hot). When the ingot gets too cold to deform without cracking, heat it up and forge again.Four separate stages of the ingot are shown here; each stage is the result of several cycles of heating and forging. A total of about 50 cycles may be needed to bang out the blade shape from the ingot—a highly labor-intensive process.Pendray uses a modern air hammer. A handheld hammer works, too, but it takes longer.
 |
6.Cut the blade to final shape andhand-forge to add finer details.
 |
7.Remove the excess steel and the decarburized surface metal. Pendray is using an electric belt grinder for this step.
 |
8.Cut grooves and drill holes into the surface of the blade to create Mohammed’s ladder and rose patterns, if desired. Forge the blade flat again and polish the surface to give the blade its near final form.
 |
9.Etch blade surface with an acid to bring out the pattern; the softer steel darkens, and the harder steel appears as brighter lines.
 |
有玫瑰纹和天梯的复制品。 |
ALL PHOTOGRAPHS BY WILLIAM ROSENTHAL
