321 austenitic stainless steel has good corrosion resistance in the atmosphere, which is widely used in petrochemical, electric power, bridge and automobile industries.But the “rust” of stainless steel is not absolute, because of the special service environment, stainless steel corrosion will occur.The medium concentration, pH value, temperature and other factors will have a great impact on the corrosion resistance of stainless steel.For example, in the sensitization temperature range of 450~850℃ for a long time, stainless steel will occur intergranular corrosion. The mechanism is that C combines with Cr at the grain boundary to form Cr23C6 and precipitates, which reduces the content of Cr at the grain boundary. This is the so-called “poor chromium”.Cr is one of the main elements to inhibit intergranular corrosion. When the content of Cr at grain boundaries is lower than 12%, the probability of intergranular corrosion will increase.
Property Of 321 Stainless Steel Tube
Countries | Standard Number | Grade | Chemical Composition,% | ||||||
C | Si | Mn | P | S | Cr | Othes | |||
≤ | |||||||||
China | GB/T 13296 | 1Cr18Ni9Ti | ≤0.12 | ≤1 | ≤2 | 0.035 | 0.03 | 17-19 |
Ti5(C 0.02 -0.8) |
ISO | ISO/PDTS 15510 | X6CrNiTi18-10 | ≤0.08 | ≤1 | ≤2 | 0.045 | 0.03 | 17-19 | Ti5C-0.7 |
USA | ASTNA213 | (S32100)321 | ≤0.08 | ≤1 | ≤2 | 0.045 | 0.03 | 17-19 |
Ti5(C+N) -0.7 |
Japan | JIS G4303-1998 | SUS 321 | ≤0.08 | ≤1 | ≤2 | 0.045 | 0.03 | 17-19 | Ti≥5C |
German | DIN 17440-1996 | X6CrNiTi18-10 | ≤0.08 | ≤1 | ≤2 | 0.045 | 0.0151) | 17-19 | Ti5C-0.7 |
DIN EN10088-1 | |||||||||
France | NF EN10088-1 | ||||||||
UK | BSEN10088-1 | ||||||||
RS970-1:1996 | 321 S31 | ≤0.08 | ≤1 | ≤2 | 0.045 | 0.03 | 17-19 | Ti 5C-0.8 |