304 stainless steel is a versatile stainless steel material with stronger anti-rust properties than 200 series stainless steel materials. It is also relatively good in terms of high temperature resistance and can reach temperatures as high as 1000-1200 degrees. 304 stainless steel has excellent stainless corrosion resistance and good intergranular corrosion resistance. For oxidizing acids, it was found in experiments that 304 stainless steel has strong corrosion resistance in nitric acid below the boiling temperature with a concentration ≤ 65. It also has good corrosion resistance to alkali solutions and most organic and inorganic acids.
Application scope:
304 is the most widely used stainless steel and heat-resistant steel. Used in food production equipment, general chemical equipment, nuclear energy, etc.
Chemical composition of 304 stainless steel
Specifications C Si Mn P S Cr Ni (nickel) Mo
Performance Specifications:
304 physical properties
Tensile strength σb (MPa) ≥ 520, conditional yield strength σ0.2 (MPa) ≥ 205, elongation δ5 () ≥ 40, The area shrinkage ψ () ≥ 60,
Hardness: 1. Refer to GB/T3280-2007 (stainless steel cold-rolled steel plates and steel strips) not greater than HBW201, HRB92, HV210, the above three are the three hardness measurement methods, Vickers hardness, Brinell hardness, etc.;
2. See GB/T4327-2007 (stainless steel hot-rolled steel plates and strips) not greater than HBW201, HRB92, HV210;
3. Refer to GB/T1220-2007 (stainless steel rods) not larger than HBW187, HRB90, HV200;
4. Refer to GB13296-2007 (stainless steel seamless steel pipes for boilers and heat exchangers) not larger than HBW217, HRB95, HV220.
304 Stainless Steel Large Picture Standard International Stainless Steel Labeling Method
The American Iron and Steel Institute uses three digits to label various standard grades of malleable stainless steel. Among them:
① Austenitic stainless steel is represented by 200 and 300 series numbers,
② Ferritic and martensitic stainless steel are represented by 400 series numbers. For example, some of the more common austenitic stainless steels
are marked with 201, 304, 316 and 310.
③ Ferritic stainless steels are marked with 430 and 446. Martensitic stainless steel is marked with 410, 420 and 440C
, dual phase (austenite-ferrite),
④ stainless steel, precipitation hardening stainless steel and iron-containing stainless steel High alloys with a weight lower than 50 are usually named by patented names or trademarks.
4)． Classification and grading of standards
4-1 Grading and classification:
①National standard GB ②Industry standard YB ③Local standard ④Enterprise standard Q/CB
4 -2 Category:
①Product standard ②Packaging standard ③Method standard ④Basic standard
4-3 Standard level (divided into three levels):
Y level : International advanced level I level: International general level H level: Domestic advanced level
4-4 national standard
GB1220-84 stainless steel bar (level I) GB4241-84 stainless steel welding disc Garden (Grade H)
GB4356-84 Stainless steel welded disk garden (Grade I) GB1270-80 Stainless steel pipe (Grade I)
GB12771-91 Stainless steel welded pipe (Grade Y) GB3280- 84 Stainless steel cold plate (Grade I)
GB4237-84 Stainless steel hot plate (Grade I) GB4239-91 Stainless steel cold strip (Grade I)