Duplex 2205 pipe is more corrosion resistant than 300 series stainless steel

Corrosion resistance

Corrosion resistance of duplex 2205 pipe is better than 304 stainless steel pipe, with good corrosion resistance in the production of pulp and paper. Moreover, 316 stainless steel is also resistant to erosion by marine and aggressive industrial atmospheres.

Heat resistance

316 stainless steel has good oxidation resistance in intermittent use below 1600 °C and continuous use below 1700 °C. In the range of 800-1575 degrees, it is preferable not to continuously apply 316 stainless steel, but when 316 stainless steel is continuously used outside this temperature range, the stainless steel has good heat resistance. 316L stainless steel has better carbide precipitation resistance than 316 stainless steel and can be used in the above temperature range.

Heat treatment

Annealing is carried out at a temperature ranging from 1850 to 2050 degrees, followed by rapid annealing and rapid cooling. 316 stainless steel cannot be hardened by heat treatment.

Welding

316 stainless steel has good welding properties. All standard welding methods can be used for welding. When welding, 316Cb, 316L or 309Cb stainless steel filler rods or welding rods can be used for welding according to the application. For best corrosion resistance, the welded section of 316 stainless steel requires post-weld annealing. If 316L stainless steel is used, post-weld annealing is not required.

304 is a versatile stainless steel that is widely used to make equipment and parts that require good overall performance (corrosion resistance and formability).

301 stainless steel exhibits significant work hardening during deformation and is used in a variety of applications where higher strength is required.

302 stainless steel is essentially a variant of 304 stainless steel with a higher carbon content, which gives it a higher strength by cold rolling.

302B is a high silicon-containing stainless steel with high resistance to high temperature oxidation.

303 and 303Se are free-cutting stainless steels containing sulfur and selenium, respectively, for applications where the main requirements are easy cutting and high gloss. 303Se stainless steel is also used to make parts that require enthusiasm, because under these conditions, this stainless steel has good hot workability.

304L is a variant of 304 stainless steel with a lower carbon content for applications requiring soldering. The lower carbon content minimizes the precipitation of carbides in the heat affected zone near the weld, which may result in intergranular corrosion (weld erosion) in certain environments.

304N is a nitrogen-containing stainless steel that is added to increase 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 critical.

308 stainless steel is used to make electrodes.

The nickel and chromium contents of 309, 310, 314 and 330 stainless steel are relatively high in order to improve the oxidation resistance and creep strength of steel at high temperatures. The 30S5 and 310S are variants of the 309 and 310 stainless steels, except for the lower carbon content, in order to minimize the carbides precipitated near the weld. 330 stainless steel has a particularly high resistance to carburizing and thermal shock resistance.

Types 316 and 317 stainless steel contain aluminum and are therefore much more resistant to pitting corrosion in marine and chemical industrial environments than 304 stainless steel. 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 steel stabilized by titanium, niobium and tantalum, respectively, and are suitable for use as welded members at high temperatures. 348 is a stainless steel suitable for the nuclear power industry, which has certain restrictions on the combination of boring and drilling.