304 Stainless Steel information
product introduction
Grade 304 is the most commonly used stainless steel. It is an austenitic, corrosion-resistant steel with excellent strength, toughness, fabrication characteristics and weldability. The low carbon version, 304L, may be required for full corrosion resistance when thicker sections are welded. The 304H version has a guaranteed minimum carbon content, which ensures good strength at high temperatures.
Grade 304 stainless steel contains 18% chromium, which makes it resistant to many corrosive environments. It is austenitic in structure because of the 8% nickel it contains. The very tough and ductile austenitic structure gives grade 304 excellent formability and fabrication characteristics.
In most applications, 304 stainless steel is used where its corrosion resistance gives long-lasting appearance and service life. The ease of cleaning and of maintaining a hygienic surface on the steel make it excellent for many purposes.
The low carbon version, 304L stainless steel, may be required for full corrosion resistance when sections thicker than about 6mm are welded. The version with guaranteed high carbon, 304H stainless steel, may be required for elevated temperature service, such as pressure vessels.
Typical Applications
Brewing and dairy equipment, evaporators, drums, barrels, heat exchangers, hospital equipment, refrigeration parts, chemical and food processing, shop fittings, bench tops, kitchens, kitchen utensils, sinks, wash troughs, urinals, hand rails, dishwashers, clothes dryers, ovens, heating trays, air conditioning equipment, guttering and rain water goods, counters and display cabinets, hot and cold food bars, commercial oven hoods, beer barrels.
standards for 20 # seamless steel pipes
(1) ASTM A276
(2) ASTM A240
(3) JIS G4305
(4) JIS G4303
304 Stainless Steel chemical composition
(AS1449 / ASTM A240 – Flat Products)
| | | Carbon | Silicon | Manganese | Phosphorus | Sulphur | Nickel | Chromium | Nitrogen |
| 304 | Specification (max) | 0.08 | 0.75 | 2.00 | 0.045 | 0.030 | 8.00 – 10.50 | 18.00 – 20.00 | 0.10 |
| | (typical) | 0.045 | 0.49 | 1.22 | 0.028 | 0.005 | 8.3 | 18.2 | 0.045 |
| 304L | Specification (max) | 0.03 | 0.75 | 2.00 | 0.045 | 0.030 | 8.00 – 12.00 | 18.00 – 20.00 | 0.10 |
| | (typical) | 0.020 | 0.42 | 1.46 | 0.028 | 0.005 | 9.1 | 18.3 | 0.048 |
| 304H | Specification (max) | 0.04 – 0.10 | 0.75 | 2.00 | 0.045 | 0.030 | 8.00 – 10.50 | 18.00 – 20.00 | – |
| | (typical) | 0.049 | 0.49 | 1.25 | 0.028 | 0.005 | 8.3 | 18.3 | 0.043 |
mechanical properties (mechanical properties)
Mechanical Properties of 304 Stainless Steel
(AS1449 / ASTM A240 – Flat Products)
| | Thickness | 0.2% Proof Stress | Tensile Strength | Elongation | Hardness |
| Unit | | MPa | MPa | % | HB (max) |
| 304 | Specification (min) | | 205 | 520 | 40 | 202 |
| | typical values | 0.3 – 3.5mm | 260 | 660 | 55 | 160 |
| | | 3.6 – 6mm | 250 | 600 | 55 | 160 |
| | | > 6mm | 240 | 580 | 55 | 155 |
| 304L | Specification (min) | | 170 | 485 | 40 | 183 |
| 304H | Specification (min) | | 205 | 520 | 40 | 202 |
