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The fabled Damascus steel, whose elusive forging process was guarded by a select few, has seen a modern-day resurgence. For centuries, this unique forging technique was feared lost to history as all known traditions of creating this superbly crafted, ornate steel disappeared.?Fortunately for professional and amateur metallurgists alike, modern technology and metallurgical science has advanced enough for scientists to discover modern ways to recreate the resilient and exquisitely intricate Damascus steel.?
The Reinvention of Damascus Steel
Feather Damascus Pattern
Named for what is now the capital city of Syria, Damascus steel was originally an undocumented forging technique utilized by Near East and Middle Eastern sword makers.?While some evidence may suggest Damascus steel dates back to 300 B.C., the first mentions of the famed steel date back to between 300 and 500 A.D.
Western Europe received its first real taste of Damascus steel during the Crusades of the 11th Century when the Crusaders witnessed the famed blade's unequivocal sharpness in action at the hands of the Arab warriors. The ferocity of those Arab warriors with their unique blades gave rise to the legends which spread throughout the Middle East and Europe.
Traditional Damascus steel is identifiable by its various swirling patterns on the flat of the blade.?The unique patterns are believed to originally be derived from blocks of Indian and Sri Lankan wootz steel. These wootz steel ingots contained a variety of “impurities” such as tungsten and vanadium that, when combined with the traditional Indian smelting process as well as the numerous rounds of layering used to prepare each blade, created the magnificent Damascus blades.??
The Arabs successfully imported the wootz ingots for centuries. However, as borders altered, wars ravaged and wootz reserves ran dry, the world began to lose touch with the masters of this unparalleled steel.?Sadly, by the mid 18th Century, the blades had disappeared as had the techniques for their creation.
A Modern-Day Reinvention
”What
Thankfully, the human race is nothing if not tenacious and nostalgic.?Metallurgists, historians and collectors from around the world coupled with drastic advances in technology have been able to reverse engineer the general Damascus steel forging process, and of course, have added their own special touches along the way.
A September 29, 1981 New York Times article revealed that two Stanford University scientists researching metals with superplastic characteristics accidentally recovered the secret to creating Damascus steel.?Their research showed that the steel used to create the ancient blades required a high carbon content and a relatively low temperature for the forging and hammering process, which then required a rapid rise in heat followed by a swift cooling.?
As an aside for those gory history buffs out there, the “quenching” or cooling process for ancient Damascus steel blades is fodder for tall tales. Legend has it that the quenching process is where the blades derived their magical strength. It was believed forgers would thrust the heated blades into slaves to transfer their strength into the blade, or that the blades were “quenched” in dragon's blood.?
While the notion of quenching the steel in blood in order to provide strength may seem unrealistic, some modern scientists believe the nitrogen in the blood may, in fact, have strengthened the alloy.
It is known, now, that Damascus steel is not a pure metal, relying on a variety of impurities and an imbuement of high carbon percentages to provide the beauty, strength and durability that is paving the way for the modern Damascus steel revival.?The plasticity of the heated metal and the durability of the cooled product allows this steel to be shaped into a wide variety of tools, from gears and auto parts to fashionable styled, high-end kitchen knives.
The Nuts and Bolts of Damascus Steel
”Forging
The creation of modern Damascus steel is still an art form.?From selecting the proper steel with the proper alloys and carbon content to varied temperatures for forging, shaping and quenching the steel, the process is extensive and precise.
For example, F.N. Sharp uses a combination of VG10 and VG2 steel to reveal a feathered Damascus pattern. VG10 contains roughly 1% carbon and molybdenum, 15% chromium, 1.5% cobalt, and less than 1% vanadium, manganese and phosphorus, while VG2 is comprised of roughly 1% carbon, 15% chromium, and less than 1% copper, molybdenum and nickel. The addition of manganese to VG10 produces a darker color steel, while the inclusion of nickel in VG2 provides a bright silver tone.
The differing elements of steel also have different purposes. For example, the addition of carbon improves a blade's hardness, edge retention, tensile strength and resistance to wear and abrasion, while the addition of manganese improves grain structure, hardenability, strength and wear resistance. The addition of chromium, which is one of the most important elements of stainless steel (at least 13% chromium is required for stainless steel) improves harness, tensile strength, and resistance to wear and corrosion.
When creating Damascus, the two steels are stacked into alternating layers to create billets which are then twisted, folded, heated and hammered. Once the billets have been repeatedly folded and hammered and the hot metal is the proper shade of dark red (light red indicates a high temperature that will lend the metal to cracking), the steel is then quenched to harden the structure.?Finally, the crafter finishes the shaping process by hammering, lengthening and flattening the metal until a unique Damascus pattern is revealed.
Types of Steel Used to Make Damascus Knives
Types of Stainless Steel for Damascus
The steel required to forge Damascus blades varies depending on the purpose of the blade.?High carbon steel, stainless steel, or a combination of both are the primary requirements. High carbon steel blades are renowned for their sharp edges, while?stainless steel blades are known for being impervious to oxidation. Some commonly used steel grades include VG1, VG2, VG10, AUS8, and AUS10.
AUS8, a Japanese steel produced by Aichi Foundry, is a stainless steel considered to be a mid-level steel when compared to the superior VG10 or AUS10. This steel has a high carbon content allowing for a hard knife but is known for requiring frequent sharpening. This edge retention issue separates knives forged of this steel from more premium quality knives forged of VG10 or AUS10.?This allows for knives of this steel to be more affordable and easily mass produced.
AUS10 is a Japanese steel also produced by Aichi Foundry.?It is a stainless steel with a hardness measured between 58 and 60 on the Rockwell scale.? While its edge retention is better than AUS8, it's still an issue for this steel.?AUS10 is similar to VG10 and is commonly used to create high-end and kitchen knives.
VG1 steel is a Japanese steel created by Takefu Special Steel Company that is primarily a stainless steel but has a higher carbon content than most other VG steels.?This steel was the predecessor to VG10. Known for being sharp and producing great edges, VG1 is lacking the addition of cobalt and vanadium, which means blades crafted from this steel are prone to chipping and corrosion.
VG2 steel, also a Takefu Special Steel Company creation, is a hard stainless steel with a 62 on the Rockwell scale.?The carbon content is lower than VG1 and VG10, but its combination with other metals such as chromium, nickel and copper make it extremely corrosive-resistant.
VG10 is a famed Japanese stainless steel also created by Takefu Special Steel Company that is combined with a specific series of other metals, including cobalt, carbon, chromium and vanadium to produce a steel that is not only free from oxidation, but is also distinctively hard, scoring between 60-62 on the Rockwell scale. VG10 is also known for holding a frighteningly sharp edge, which makes it one of the most revered steels on the market for kitchen knives.