three hundred and four It is universal Stainless steel pipe It is widely used to make equipment and parts with good comprehensive performance (corrosion resistance and formability). 301 stainless steel presents obvious work hardening phenomenon during deformation, which is used in various occasions requiring higher strength.
??? 302 stainless steel is essentially higher in carbon content 304 stainless steel The high strength can be obtained by cold rolling.
??? 302B is a kind of stainless steel with high silicon content, which has high oxidation resistance at high temperature.
??? 303se and 303se are free cutting stainless steels containing sulfur and selenium, respectively. They are used in situations where easy cutting and high gloss are required. 303se stainless steel is also used to make machine parts requiring hot upsetting because it has good hot workability under such conditions.
??? 304L is a variant of 304 stainless steel with low carbon content, which is used for welding. The lower carbon content makes the carbides precipitated in the heat affected zone near the weld to a minimum, and the precipitation of carbides may cause intergranular corrosion (welding corrosion) of stainless steel in some environments.
??? 304n is a kind of stainless steel containing nitrogen. The purpose of adding nitrogen is to improve the strength of steel.
??? 305 and 384 stainless steels contain high nickel, and their work hardening rate is low, so they are suitable for various occasions with high requirements for cold formability.
??? 308 stainless steel is used for welding rod.
??? The contents of Ni and Cr in 309, 310, 314 and 330 stainless steels are relatively high in order to improve the oxidation resistance and creep strength of the steels at high temperature. And 30s5 and 310S It is a variety of 309 and 310 stainless steel, but the difference is that the carbon content is low, so as to minimize the carbide precipitated near the weld. 330 stainless steel has high carburizing resistance and thermal shock resistance
??? Type 316 and 317 stainless steels contain aluminum, so their pitting corrosion resistance in marine and chemical industry environments is much better than that of 304 stainless steel. Among them, the varieties of 316 stainless steel include low carbon stainless steel 316L, high strength stainless steel 316N containing nitrogen and free cutting stainless steel 316F with high sulfur content.
??? 321, 347 and 348 are stainless steels stabilized with titanium, niobium plus tantalum and niobium respectively. They are suitable for welding at high temperature. 348 is a kind of stainless steel which is suitable for nuclear power industry.