Why Stainless steel is corrosion Resistant?
Why Stainless steel is corrosion Resistant? Stainless steel is known for its corrosion resistance in many environments in which carbon and low alloy tool steels would corrode. These steels also tolerate the corrosive attack of various acids, they retain strength and toughness at both ends of the temperature scale yet can be fabricated into complex shapes for numerous uses. It is because of this exceptional versatility, stainless steel warrants careful consideration for any product where one of these six key requirements are involved. u2022tCorrosion Resistance u2022tStrength at Elevated Temperatures u2022tStrength and Ductility at Cryogenic Temperatures u2022tOxidation Resistance at High Temperatures u2022tAppearance u2022tAbrasion Resistance Stainless steel contains iron, chromium, manganese, silicon, carbon and, in many cases, significant amounts of nickel and molybdenum. These elements react with oxygen from water and air to form a very thin, stable film that consists of such corrosion products as metal oxides and hydroxides. Chromium plays a dominant role in reacting with oxygen to form this corrosion product film. In fact, all stainless steels by definition contain at least 10 percent chromium. The more chromium that is added, the more stable the passive layer becomes, and the better the corrosion resistance. Other elements such as nickel, manganese, and molybdenum can be added to enhance stainless steel corrosion resistance. Corrosion resistance is greatest when the steel is boldly exposed and the surface is maintained free of deposits. If passivity is destroyed under conditions that do not permit restoration of the passive film, then stainless steel will corrode much like a carbon or low-alloy steel. For example, covering a portion of the surface u2013 for example, by biofouling, painting, or installing a gasket u2013 produces an oxygen-depleted region under the covered region. During the fabrication of Stainless-steel components or structures it is possible to degrade the corrosion resistance. This occurs when austenitic stainless steels (e.g. 304) are exposed to temperatures between about 425 u00b0C (797 u00b0F) and 870 u00b0C (1598 u00b0F). If the exposure time is too long, then the areas near the metalu2019s grain boundaries lose their corrosion resistance and can be preferentially attacked when exposed to a corrosive environment. Stainless steelu2019s resistance to corrosion, staining, low maintenance, rather inexpensive, and well-known shine make it a perfect base material for a variety of applications. Stainless steel is 100% recyclable. Over 50% of new stainless steel is made from remelted scrap metal, characterizing it as a rather eco-friendly material. Stainless steel does not rust because it is sufficiently reactive to protect itself from further attack by forming a passive corrosion product layer. Because of its durability and aesthetic appeal, stainless steel is used in a wide variety of products. Visit http://santoshsteels.com/ for stainless steel pipe manufacturers in india, manufacturers of stainless steel pipes in india, industrial pipe manufacturers in india, stainless steel tubes manufacturer in india, s s pipe manufacturer in india, stainless steel pipe Suppliers in india, Suppliers of stainless steel pipes in india, industrial pipe Supplier in india, s.s pipe exporter in india, stainless steel pipes and tubes manufacturers in india, stainless steel pipes and tubes Supplier in india, stainless steel pipes and tubes exporter in india.
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