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Stainless steel alteration caused in various areas

Submitted by cyrusfrank on Fri, 07/10/2020 - 21:11

After curing the hardening, the hardness achieved by this material is not as high as that provided by 420 Stainless Steel Tube. Main applications of 410 stainless in oil refining equipment, valves, pump components and cutlery.
 
By increasing the amount of sulfur, the stainless 420 F, and a variety of 420, are obtained, with good susceptibility to machines.
 
Carbon additives (for higher hardness), chromium and molybdenum (also improve wear resistance) lead us to the Martensitic 440 type stainless steel, used for professional cutting knives.
 
Stainless steel from iron
 
Stainless steel from iron is also magnetic. Although carbon is less than martensitics, it becomes partly austenitic at high temperatures and thus Martent precipitated during cooling. Arguably partially treatable by heat treatment.
 
Iron stainless steels generally have higher chromium content than martensitics. This increase in the amount of chromium improves the wear resistance of various media, but it partially sacrifices other properties, such as shock resistance.
 
The most commonly used type Stainless Steel Capillary Tubeis type 430, which contains 16 to 18% chromium and a maximum of 0.12% carbon. Among its applications, we can mention: tableware, dishes, kitchens, sinks, coins, paints and coolers.
 
One of the biggest problems with 430 stainless steel is the loss of ductility in the welded areas, which are usually brittle
 
Significant increases in nickel lead to Ni-Cr-Fe alloys, as the element with the greatest presence in the substance is no longer iron but rather nickel. These materials are not known as stainless steels but their alloys are made of nickel and have excellent corrosion resistance in various mediums at high temperatures. The high nickel content ensures good corrosion resistance.
 
The Stainless Steel Corrugated Tubeis an excellent ductility material. For additional deep sealing cases, the increased nickel content allows for improved ductility. For this purpose, type 305 has been developed.
 
Minor cuts in the nickel content reduce the stability of austenite, which allows the appearance of martensite caused by cold deformation, thereby achieving excellent properties for structural applications. Its 301 type, available in 1/4, 1/2, 3/4 versions and is quite tough and widely used in railway, urban train and bus chassis industries.
 
Type 303 results in increased sulfur duration in 304 in order to improve manufacturing capacity. Softness and wear resistance are affected by this increase in the amount of sulfur.
 
It produces Stainless Steel Coil Tubingsteel with partial nickel substitution of manganese. It is used in structural applications, providing less than 301 corrosion resistance.

Alteration caused by stainless steel in various areas
Phosphoric acid: in general terms, the resistance to it is quite good but care must be taken with impurities and in particular with hydrofluoric acid.
Acid sulphites: the corrosion caused by this type of solutions can be catastrophic, as it happens with certain litter bins since they contain many impurities. In these cases, molybdenum alloys are preferable.
Hydrochloric acid: Corrosion increases as the acid concentration increases, therefore it is convenient to avoid this association.
Organic acids: in general, these acids are not as corrosive as mineral acids or those used in food industry (acetic, oxalic, citric acids, etc.); these are practically harmless.
Alkaline solutions: cold solutions have practically no effect, but the same does not happen when the solutions are concentrated and hot.