Overview
Compared with 304 (06Cr19Ni10) and 304L, 304H is mainly different in carbon content. 304H has a higher carbon content than 304, and 304L has a lower carbon content than 304. The carbon content of 304 is within 0.08%, and the carbon content of 304H (07Cr19Ni10) is between 0.04-0.1%. The carbon content of 304L (022Cr19Ni10) is 0.035%, and the content of other elements is basically the same.
ASTM A213 Grade304H stainless steel tube which heat-resistant, in the solid solution state, has good intergranular corrosion resistance, plasticity, toughness, cold workability, good bending and welding process performance; The corrosion resistance, high durability and structure stability, cold deformation ability is pretty good. It has also good corrosion resistance in oxidizing acid, atmosphere, water and other media. It's suitable for manufacturing deep-drawn parts and acid pipelines, containers, etc. The operating temperature can reach up to 650℃, and the anti-oxidation temperature can reach up to 850℃3041. The type material has the characteristics of good weaving and splicing due to its low carbon content.
Specification
ASTM A213/A213M-21a Standard Specification for Seamless Ferritic and Austenitic Alloy-Steel Boiler, Superheater, and Heat-Exchanger Tubes.
Chemical Composition
| Grade | C | Mn | Si | P | S | Cr | Mo | Ni | N | |
| 304 | min. | - | - | - | - | - | 18.0 | - | 8.0 | - |
| max. | 0.08 | 2.0 | 0.75 | 0.045 | 0.030 | 20.0 | 10.5 | 0.10 | ||
| 304L | min. | - | - | - | - | - | 18.0 | - | 8.0 | - |
| max. | 0.030 | 2.0 | 0.75 | 0.045 | 0.030 | 20.0 | 12.0 | 0.10 | ||
| 304H | min. | 0.04 | - | - | -0.045 | - | 18.0 | - | 8.0 | - |
| max. | 0.10 | 2.0 | 0.75 | 0.030 | 20.0 | 10.5 | ||||
Mechanical Properties
| Grade | Tensile Strength (MPa) min | Yield Strength 0.2% Proof (MPa) min | Elongation (% in 50mm) min | Hardness | |
| Rockwell B (HR B) max | Brinell (HB) max | ||||
| 304 | 515 | 205 | 40 | 92 | 201 |
| 304L | 485 | 170 | 40 | 92 | 201 |
| 304H | 515 | 205 | 40 | 92 | 201 |
Physical Properties
| Grade | Density (kg/m3) | Elastic Modulus (GPa) | Mean Coefficient of Thermal Expansion (μm/m/°C) | Thermal Conductivity (W/m.K) | Specific Heat 0-100°C (J/kg.K) | Electrical Resistivity (nΩ.m) | |||
| 0-100°C | 0-315°C | 0-538°C | at 100°C | at 500°C | |||||
| 304/L/H | 8000 | 193 | 17.2 | 17.8 | 18.4 | 16.2 | 21.5 | 500 | 720 |
Applications
The grade 304H steel can be made into plates, sheets, and coils to be used in the following:
- 1. Food processing equipment, particularly in beer brewing, milk processing & wine making.
- 2. Kitchen benches, sinks, troughs, equipment and appliances
- 3. Architectural panelling, railings & trim
- 4. Chemical containers, including for transport
- 5. Heat Exchangers
- 6. Woven or welded screens for mining, quarrying & water filtration
- 7. Threaded fasteners
- 8. Springs
