321 VS 304 VS 304L Difference Between 321 and 304 304L

TP321 TP321H stainless steel is basically from 304 stainless steel. They different by a very very small addition of Titanium. The real difference is their carbon content. The higher the carbon content the greater the yield strength. 321 stainless steel has advantages in a high temperature environment due to its excellent mechanical properties. Compared with 304 alloy, 321 stainless steel has better ductility and resistance to stress fracture. In addition, 304L can also be used for anti-sensitization and intergranular corrosion.

Grade TP304L is more readily available in most product forms, and so is generally used in preference to 321 if the requirement is simply for resistance to intergranular corrosion after welding. However 304L Stainless Steel Tubes has lower hot strength than 321 stainless steel tube and so is not the best choice if the requirement is resistance to an operating environment over about 500°C.

However, 321 is a much better option in operating temperature environments in excess of 500° C and therefore has its own merits. Alloy 321 stainless steel tube is also advantageous for high temperature service because of its good mechanical properties. Alloy 321 stainless steel offers higher creep and stress rupture properties than Alloy 304 and, particularly, Alloy 304L also be considered for exposure where sensitization and intergranular corrosion are concern.

Guanyu Tube is specialized manufacturer of ASME SA213 TP321 and ASME SA213 TP304L Stainless Steel tubes in China.