Simple classification of stainless steel 300 series and its main uses

Simple Classification of Stainless Steel

Stainless steel can be simply divided into three categories: 200 series, 300 series and 400 series, of which 300 series is the most commonly used, 200 series and 400 series are, to some extent, substitutes for 300 series, and strictly speaking, 400 series is not called stainless steel, called stainless steel, because it does not contain nickel. The 200 series and 300 series contain nickel.

300 series can be briefly divided into 304, 304L, 316, 316L, 321, 309S, 310S, etc., the distinction is based on the content of various metal elements, the content of different stainless steel characteristics are not the same, 304 and 304L is the difference between the carbon (C) content of the different, with the L is said to be low carbon, also known as low carbon, 316 and 316L is the difference between the same. The difference between 316 and 316L is also the same.

304 is the most common varieties of 300 series, so generally from the price change of 304 can judge the price trend of the whole stainless steel. 200 series contains less nickel, 400 series does not contain nickel, 300 series contains the most nickel, so by the price of nickel is the most affected by the 300 series.

Characteristics and uses of the types

304: as a wide range of uses of steel, with good corrosion resistance, heat resistance, low temperature strength and mechanical properties, stamping, bending and other hot workability, no heat treatment hardening phenomenon, non-magnetic, using temperature of minus 193 degrees to positive 800 degrees.

Uses:tableware, kitchenware, water heater, boiler, automobile parts, medical equipment, food machinery, storage of wine utensils, pressure vessels (chemical machinery, chemical equipment).

304L as a low carbon 304 steel, in the general state, corrosion resistance and 304 is almost the same, but after welding and stress relief, it is good resistance to intergranular corrosion, in the absence of heat treatment, but also maintains good corrosion resistance, generally used at 400 degrees.

321 in 304 steel to add Ti elements to prevent intergranular corrosion, suitable for positive 430 to below 900 degrees, non-magnetic.

Uses: automobile exhaust, heat exchangers, containers and other products that are not heat-treated after welding, due to the addition of Ti elements, it is not suitable for making food processing equipment.

316 low carbon, add MO elements, so his corrosion resistance and atmospheric corrosion resistance and high temperature strength performance is particularly good, can be used in harsh conditions, suitable for use below 900 degrees, non-magnetic.

Uses: equipment used in seawater, chemicals, dyes, paper, acetic acid, fertilizers and other production equipment, food industry and coastal area facilities, products with special requirements for inter-crystalline corrosion.

309S/310S these two materials, nickel and chromium content is relatively high, while increasing the content of Si, so that it has a high temperature and corrosion resistance, of which 309S can withstand the repeated heating below 980, 310S use the temperature reaches 1200 degrees, the continuous use of the temperature can be in 1150 degrees, non-magnetic.

Use: Applicable to high-temperature furnace equipment, drying equipment and other key parts, furnace materials, aviation, petrochemical, electric power and so on.