321 STAINLESS STEEL COIL

321 stainless steel is a Ni-Cr-Mo type austenitic stainless steel. Its performance is very similar to that of 304 stainless steel, but due to the addition of metal titanium, it has better resistance to intergranular corrosion and high temperature strength. Due to the addition of metal titanium, the formation of chromium carbide is effectively controlled.

321 austenitic stainless steel has good corrosion resistance in the atmosphere and is widely used in industries such as petrochemicals, electricity, bridges and automobiles. However, the "stainlessness" of stainless steel is not absolute. Due to the special service environment, stainless steel will also corrode. Factors such as medium concentration, pH value, and temperature will have a great impact on the corrosion resistance of stainless steel. For example, if used for a long time in the sensitization temperature range of 450~850℃, stainless steel will suffer from intergranular corrosion. The mechanism is that C combines with Cr at the grain boundary to form Cr23C6 and precipitate, which reduces the Cr content at the grain boundary. This is the so-called "chromium depletion". Cr is one of the main elements that inhibit intergranular corrosion. When the Cr content at the grain boundary is less than 12%, the probability of intergranular corrosion will increase.

INDUSTRY APPLICATIONS

1. Petroleum waste gas combustion pipeline

2. Engine exhaust pipe

3. Boiler shell, heat exchanger, heating furnace parts

4. Diesel engine silencer parts

5. Boiler pressure vessel

6. Chemical transport vehicle

7. Expansion joint

8. Spiral welded pipe for furnace pipeline and dryer