How much do you know about 300 series stainless steel?

Stainless steelrefers to steel that is resistant to corrosion by weakly corrosive media such as air, steam, and water, and chemically corrosive media such as acid, alkali, and salt. In practical applications, steels resistant to weakly corrosive media are often referred to as stainless steel, and steels resistant to chemical media are referred to as acid-resistant steel. Due to the difference in chemical composition between the two, the former is not necessarily resistant to corrosion by chemical media, while the latter are generally stainless. The corrosion resistance of stainless steel depends on the alloying elements contained in the steel.

According to the American AISI standard, stainless steel is represented by three Arabic numerals. The first digit indicates the category, and the second and third digits indicate the sequence number. The numbers are different, and the type of steel is also very different. Take the first number:

2: Cr-Ni-Mn; (200 series Stainless Steel)

3: Cr-Ni; (300 series Stainless Steel)

4: Cr; (400 series Stainless Steel)

5: Low Cr series;

6: Precipitation hardening system.

Speaking of stainless steel, the most popular model is 304, let's introduce it below.

300 series stainless steel:

In stainless steel, there are two opposing forces acting simultaneously: ferrite-forming elements continuously form ferrite, and austenite-forming elements continuously form austenite. The relative amounts of these two elements determine the final structure of the stainless steel crystal. In the process of adding austenite-forming element-nickel to the iron-chromium stainless steel, as the nickel content increases, the austenite formed will gradually increase until all ferrite structures are transformed into austenite structures In this way, 300 series stainless steel is formed.

Ronsco Supplier Stainless Steel Products

At present, the common grades of 300 series stainless steel are:

1.304 low carbon austenitic stainless acid-resistant steel

Performance: General resistance to intergranular corrosion and excellent corrosion resistance. It has certain resistance to alkali and most organic and inorganic acids.

Uses: It is widely used in decoration and acid pipelines, chemical equipment, etc. Currently, there are a large number of high-quality304 stainless steelin the hot stainless platform.

2.304L low carbon austenitic stainless acid-resistant steel

Performance: Good resistance to crystal and corrosion, good resistance to various strong corrosive media.

Uses: Suitable for petrochemical corrosion resistant equipment parts, especially welded pipe fittings that cannot be heat treated after welding.

3.304H austenitic stainless heat-resistant steel

Performance: Good corrosion resistance and welding performance, good heat resistance.

Uses: Mainly used in large boiler superheater, reheater, steam pipeline, petrochemical heat exchanger.

4.316 austenitic stainless hot-strength steel

Performance: Good corrosion resistance and pitting resistance to a variety of inorganic acids, organic acids, alkalis, salts, and good variable strength at high temperatures.

Uses: Suitable for large boiler superheater, reheater, steam pipe, petrochemical heat exchanger pipe fittings, can be used as pitting corrosion resistant material.


5.316L ultra-low carbon austenitic stainless acid-resistant steel

Performance: Good resistance to crystal and corrosion, good resistance to organic acids, alkalis and salts.

Uses: Widely used in acid pipelines and chemical equipment.

6.321 austenitic stainless acid-resistant steel

Performance: It has high corrosion resistance between crystals and has good corrosion resistance to some organic and inorganic acids.

Uses: Used in the manufacture of acid resistant pipelines, superheaters, reheaters, steam pipes, petrochemical heat exchangers, etc.


7.317L austenitic stainless acid-resistant steel

Performance: Excellent corrosion resistance, better pitting resistance in chloride-containing solutions. Uses: Mainly used in the manufacture of synthetic fibers, petrochemicals, textiles, papermaking and atomic energy post-processing industrial equipment.

Ronsco as an 23+ years Stainless Steel Supplier has the international advanced special metallurgical capabilities, including the German ALD 6 tons of vacuum induction furnace,6 tons of vacuum consumable furnace,18 tons of protective atmosphere ingot electroslag furnace and 1 ton vacuum induction furnace,3 tons of electroslag furnace,18 tons of evacuated ingot electroslag furnace, and 20 tons IF furnace /Purification furnace /AOD / LF / VOD refining production line,25MN / 8MN fast forging machine,450/320 rolling mill and so on.