904L Bolt, Bolts (904L)
1. Standard: DIN912, ASME B 18.2.1 /DIN931/DIN933/A325/
2. Material: 1.4529, 904L
3. Size: M8-64mm
4. Delivery time: 7-30 days
5. Chemical composition,
00Cr20Ni25Mo4.5Cu/UNS: N08904/EN: 1.4539, 904L% C≤ 0.03, Si≤ 1.00, Mn≤ 2.00, P≤ 0.035, S≤ 0.03, Ni: 23.0-25.0, Cr: 18.0-20.0, Mo: 3.0-4.0, Cu: 4.0-5.0

904L Fasteners with World Wide Shipping

904L, is a non-stabilised low carbon high alloy austenitic stainless steel. The addition of copper to this grade gives it greatly improved resistance to strong reducing acids, particularly sulphuric acid. It is also highly resistant to chloride attack - both pitting / crevice corrosion and stress corrosion cracking.
This grade is non-magnetic in all conditions and has excellent weldability and formability. The austenitic structure also gives this grade excellent toughness, even down to cryogenic temperatures. Due to its intrinsic anti-corrosive properties, 904L can be made into bolts, nuts, washers, studs, socket head cap screws, as well as a wide variety of other fasteners.

904L does have very substantial contents of the high cost ingredients nickel and molybdenum. Many of the applications in which this grade has previously performed well can now be fulfilled at lower cost by duplex stainless steel 2205 (S31803 or S32205), so it is used less commonly than in the past.

Although originally developed for its resistance to sulphuric acid it also has a very high resistance to a wide range of environments. A PRE of 35 indicates that the material has good resistance to warm sea water and other high chloride environments. High nickel content results in a much better resistance to stress corrosion cracking than the standard austenitic grades. Copper adds resistance to sulphuric and other reducing acids, particularly in the very aggressive "MID concentration" range.

In most environments 904L has a corrosion performance intermediate between the standard austenitic grade 316L and the very highly alloyed 6% molybdenum and similar "super austenitic" grades. In aggressive nitric acid 904L has less resistance than molybdenum-free grades such as 304L and 310L. For maximum stress corrosion cracking resistance in critical environments the steel should be solution treated after cold work