Page 32247 ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 通常モードに戻る ┃ INDEX ┃ ≪前へ │ 次へ≫ ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ ▼Stainless steel jew ProoppySype 08/8/11(月) 17:19 ─────────────────────────────────────── ■題名 : Stainless steel jew ■名前 : ProoppySype <tateraraadupt@lugarus.com> ■日付 : 08/8/11(月) 17:19 ■Web : http://www.swagvault.com -------------------------------------------------------------------------
In metallurgy, stainless steel is defined as a steel alloy with a minimum of 11.5 wt% chromium content.<>] Stainless steel jewelry does not stain, corrode or rust as easily as ordinary steel (it "stains less"), but it is not stain-proof. It is also called corrosion resistant steel when the alloy type and grade are not detailed, particularly in the aviation industry. There are different grades and surface finishes of stainless steel to suit the environment to which the material will be subjected in its lifetime. Common uses of stainless steel are cutlery and watch straps. Stainless steel differs from carbon steel by amount of chromium present. Carbon steel rusts when exposed to air and moisture. This iron oxide film is active and accelerates ]A few corrosion-resistant iron artifacts survive from antiquity. A famous (and very large) stainless steel jewelry wholesale example is the Iron Pillar of Delhi, erected by order of Kumara Gupta I around the year AD 400. However, unlike stainless steel, these artifacts owe their durability not to chromium, but to their high phosphorus content, which together with favorable local weather conditions promotes the formation of a solid protective nordstrom passivation layer of iron oxides and phosphates, rather than the non-protective, cracked rust layer that develops on most ironwork. The corrosion resistance of iron-chromium alloys was first recognized in 1821 by the French metallurgist Pierre Berthier, who noted their resistance against attack by some acids and suggested their use in cutlery. However, the metallurgists of the 19th century were unable to produce the combination of low carbon and high chromium Stainless steel jewelry found in most modern stainless steels, and the high-chromium alloys they could produce were too brittle to be of practical interest. This situation changed in the late 1890s, when Hans Goldschmidt of Germany developed an aluminothermic (thermite) process for producing carbon-free chromium. In the years 1904ィC1911, several researchers, particularly Leon Guillet of France, prepared alloys that would today be considered stainless steel. In Germany, Friedrich Krupp Germaniawerft built the 366-ton sailing yacht Germania featuring a chrome-nickel steel hull in 1908.<>] In 1911, Philip Monnartz reported on the relationship between the chromium content and corrosion resistance. On October 17, 1912, Krupp engineers Benno Strauss and Eduard Maurer patented austenitic stainless steel.<>] Similar industrial developments were taking place contemporaneously in the United States, where Christian Dantsizen and Frederick Becket were industrializing ferritic stainless. Harry Brearley of the Brown-Firth research laboratory in Sheffield, England is commonly credited as the "inventor" of stainless steel. In 1913, while seeking an erosion-resistant alloy for gun barrels, he discovered and subsequently industrialized a martensitic stainless steel alloy. The discovery was announced two years later in a January 1915 newspaper article in the New York Times.<>] This was latter marketed under the "Staybrite" brand by Firth Vickers in England and was used for the new entrance canopy for the Savoy Hotel in 1929 in London.<>] Properties High oxidation-resistance in air at ambient temperature are normally achieved with additions of a minimum of 13% (by weight) chromium, and up to 26% is used for harsh environments.<>] The chromium forms a passivation layer of chromium(III) oxide (Cr2O3) when exposed to oxygen. The layer is too thin to be visible, which means that the metal remains lustrous. It is, however, impervious to water and air, protecting the metal beneath. Also, this layer quickly reforms when www.steels.comthe surface is scratched. This phenomenon is called passivation and is seen in other metals, such as aluminium and titanium. When stainless steel parts such as nuts and bolts are forced together, the oxide layer can be scraped off causing the parts to weld together. When disassembled, the welded material may be torn and pitted, an effect that is known as galling. This destructive galling can be best avoided by the use of dissimilar materials, e.g. bronze to stainless steel, swing stock or even di fferent types of stainless steels (martensitic against austenitic, etc.), when metal-to-metal wear is a concern. In addition, Nitronic alloys (trademark of Armco, Inc.) reduce the tendency to gall through selective alloying with manganese and nitrogen. Nickel also contributes to passivation, as do other less commonly used ingredients such as molybdenum and vanadium. Commercial value of stainless steel The pinnacle of New York's Chrysler Building is clad with type 302 stainless steel.<>] An art deco sculpture on the Niagara-Mohawk Power building in Syracuse, New York Pipes and fittings made of stainless steelStainless steel's resistance to corrosion and staining, low maintenance, relative inexpense, and familiar luster make it an ideal base material for a host of commercial applications. There are over 150 grades of stainless steel, of which fifteen are most common. The alloy is milled into coils, sheets, plates, bars, wire, and tubing to be used in cookware, cutlery, hardware, surgical instruments, major appliances, industrial equipment, a structural alloy in automotive and aerospace assembly and building material in skyscrapers and other large buildings. stainless steel body jewelryOrange juice tankers (sometimes also other chemical tankers) often have their tanks made of stainless steel. The Parliament House of Australia in Canberra has a stainless steel flagpole weighing over 220 tonnes. The aeration building in the Edmonton Stainless steel jewelry Composting Facility, the size of 14 NHL hockey rinks, is the largest stainless steel building in North America. <>] The United States Air Force Memorial has an austenitic stainless steel structural skin. <Mozilla/4.0 (compatible- MSIE 6.0- Windows NT 5.1- SV1- .NET CLR 1.1.4322@122.200.96.98> |