Q&A
Introduction to the basic characteristics of stainless steel
Stainless steel has the ability to resist atmospheric oxidation--- that is, stainless steel, and also has the ability to corrode in media containing acid, alkali and salt--- that is, corrosion resistance. However, the size of its corrosion resistance is changed with the chemical composition of the steel itself, the state of the interaction, the use conditions and the type of environmental medium. For example, 304 steel pipe, in a dry and clean atmosphere, has absolutely excellent rust resistance, but if it is moved to the coastal area, it will soon rust in the sea fog containing a lot of salt; The 316 steel pipe performed well. Therefore, not any kind of stainless steel can resist corrosion and rust in any environment.
There are still many types of aluminum alloy and stainless steel, don't think that stainless steel will not rust, give the number of stainless steel and a simple description as follows:
301 stainless steel exhibits significant work hardening upon deformation and is used in a variety of applications where high strength is required.
302 stainless steel is essentially a variant of 304 stainless steel with a higher carbon content, which can be obtained by cold rolling.
302B is a stainless steel with a high silicon content, which has high resistance to high-temperature oxidation.
303 and 303Se are free-cutting stainless steels containing sulphur and selenium respectively, and are used in applications where easy machinability and high gloss are required.
303Se stainless steel is also used in the manufacture of parts that require hot heading, as it has good thermal workability under such conditions.
304 is a versatile stainless steel that is widely used in equipment and parts that require good overall properties (corrosion resistance and formability).
304L is a variant of 304 stainless steel with a lower carbon content and is used where welding is required. The lower carbon content minimizes the precipitation of carbides in the heat-affected zone close to the weld, which can lead to intergranular corrosion (weld erosion) in stainless steel in certain environments.
304N is a nitrogen-containing stainless steel, and nitrogen is added to improve the strength of the steel.
305 and 384 stainless steels contain high nickel and have a low work hardening rate, making them suitable for a wide range of applications where cold formability is required.
308 stainless steel is used to make welding rods.
309, 310, 314 and 330 stainless steels have relatively high nickel and chromium content in order to improve the oxidation resistance and creep strength of the steel at high temperatures. 30S5 and 310S are variants of 309 and 310 stainless steel, but with a lower carbon content to minimize carbide precipitation near the weld. 330 stainless steel has a particularly high resistance to carburizing and thermal shock.
Type 316 and 317 stainless steels contain aluminum, which makes them significantly more resistant to pitting corrosion than 304 stainless steel in marine and chemical industry environments. Among them, 316 stainless steel variants include low-carbon stainless steel 316L, nitrogen-containing high-strength stainless steel 316N, and high-sulfur free-cutting stainless steel 316F.
321, 347 and 348 are stainless steels stabilized with titanium, niobium and tantalum and niobium respectively, which are suitable for use as welding components at high temperatures.
348 is a stainless steel suitable for the nuclear power industry, and there is a certain limit on the amount of tantalum and drill combined.
