subject: Different Types Of Stainless Steel Fittings [print this page] Stainless Steel fittings, also known as inox steel or inox are defined as steel alloy fittings with a minimum of 10.5 or 11% chromium content by mass. Stainless Steel fittings do not stain, corrode or rust as easily as steel fittings, but its not stain-proof. When the alloy type and grade are not detailed its called corrosion-resistant steel or CRES. These particular fittings are popular in the aviation industry. To suit the environment to which the material will be subjected in its lifetime, manufactures use different grades and surface finishes of stainless steel. Stainless steel fittings are used where both the properties of steel and resistance to corrosion are required. The difference between carbon steel and stainless steel is the amount of chromium present. For example, carbon steel rusts when exposed to air and moisture. By forming more iron oxide, iron oxide film becomes active and accelerates corrosion. To prevent further surface corrosion and blocks corrosion from spreading into the metals internal structure stainless steel fittings contain sufficient chromium to form a passive film of chromium oxide. Resistance to corrosion and staining, low maintenance, relatively low cost, and familiar luster make stainless steel fittings ideal for a use with commercial applications. Over 150 grades of stainless steel available, but only fifteen are most commonly used. Stainless steel used in large variety of applications. Stainless steel is one hundred percent recyclable.
Different types of stainless steel fittings are available. For example, when nickel is added, the austenite structure of iron is stabilized. This crystal structure makes steels virtually non-magnetic and less brittle at low temperatures. If you want greater hardness and strength, more carbon is added. Significant quantities of manganese used in many stainless steel compositions. Just like nickel, manganese preserves an austenitic structure in the steel, but at a lower cost. It is also possible to classify stainless steel by crystalline structure. For example, austenitic, or 300 series, make up over seventy percent of total stainless steel production. This kind of stainless steel contain a maximum of 0.15% carbon, a minimum of sixteen percent chromium and sufficient nickel and/or manganese to retain an austenitic structure at all temperatures from the cryogenic region to the melting point of the alloy. Stainless steel that often used in flatware commonly known as 18/10, which is typical composition of eighteen percent of chromium and ten percent of nickel. To avoid corrosion problems caused by welding, low-carbon versions, for example 316L or 304L, are used. When biocompatibility is require, grade 316LVM is preferred. The letter L means that the carbon content of the alloy is below 0.03% which causes reduction of sensitization effect caused by the high temperatures involved in welding. It is also possible to apply standard mill finishes to flat rolled stainless steel directly by the rollers and by mechanical abrasives. First, steel is rolled to size and thickness and the annealed to change the properties of the final material. Formed oxidation can be removed by pickling, and a passivation layer is created on the surface. A final finish then applied to achieve the desired aesthetic appearance.
