Kanakratna steelage is a renowned exporter, manufacturer, stockist, supplier, and stockholder of high-quality Stainless Steel Alloy Seamless Tubes. These tubes are celebrated for their excellent corrosion resistance, durability, and high strength, making them ideal for a wide range of applications including petrochemical, pharmaceutical, food processing, and marine industries. Stainless steel alloy tubes maintain their integrity and performance across various temperature ranges and environments, offering superior weldability and ease of fabrication. This ensures reliable and long-lasting performance in even the most challenging conditions.
UNS NO8904, commonly known as 904L, is a low carbon high alloy austenitic stainless steel which is widely used in applications where the corrosion properties of AISI 316L and AISI 317L are not adequate.
The addition of copper to this grade gives it corrosion resistant properties superior to the conventional chrome nickel stainless steels, in particular to sulphuric, phosphoric and acetic acids. However, there is limited use with hydrochloric acids. It also has a high resistance to pitting in chloride solutions, a high resistance to both crevice and stress corrosion cracking. Alloy 904L performs better than other austenitic stainless steels due to the higher alloying of nickel and molybdenum.
The grade is non-magnetic in all conditions and has excellent formability and weldability. The austenitic structure also gives this grade excellent toughness, even down to cryogenic temperatures.
The high chromium content promotes and maintains a passive film which protects the material in many corrosive environments.904L has a greater resistance to precipitation of ferrite and sigma phases on cooling and welding than other stainless steels containing molybdenum such as 316L and 317L. There is no risk of intercrystalline corrosion on cooling or welding due to the low carbon content. Its maximum service temperature is at 450°C.
This grade is particularly useful in control and instrumentation tubing applications where 316 and 317L are not suitable.
Technical Specifications
| CHEMICAL COMPOSITION (% by weight) | ||
|---|---|---|
| Element | Min | Max |
| C | - | 0.2 |
| Mn | - | 2 |
| Ni | 23 | 28 |
| Cr | 19 | 23 |
| S | - | 0.03 |
| Mo | 4 | 5 |
| N | - | 0.1 |
| Cu | 1 | 2 |
| P | - | 0.03 |
| Si | - | 1 |
| MECHANICAL PROPERTIES | ||
|---|---|---|
| Temper | Annealed | |
| Tensile Rm | 71 | ksi (min) |
| Tensile Rm | 490 | MPa (min) |
| R.p. 0.2% Yield | 32 | ksi (min) |
| R.p. 0.2% Yield | 220 | MPa (min) |
| Elongation (2” or 4D gl) | 35 | % (min) |
| PHYSICAL PROPERTIES (Room Temperature) | ||
|---|---|---|
| Specific Heat (0-100°C) | 450 | J.kg-1.°K-1 |
| Thermal Conductivity | 11.5 | W.m -1.°K-1 |
| Thermal Expansion | 15.8 | mm/m/°C |
| Modulus Elasticity | 190 | GPa |
| Electrical Resistivity | 9.52 | Ohm-cm |
| Density | 7.95 | g/cm3 |