904L - Fine Tubes - #1

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w w w. f i n e t u b e s . c o m Introduction UNS N08904, commonly known as 904L, is a 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 alloy content of this material gives it corrosion resistant properties superior to the conventional chrome nickel stainless steels. In brief 904L has: • a high resistance to general corrosion, in particular sulphuric, phosphoric and acetic acids • a high resistance to pitting in chloride solutions Specification In tube and pipe 904L material can be supplied to the following specifications and analyses: ASTM B677 UNS08904 Seamless Tube & Pipe ASTM B674 UNS08904 Welded tube Werkstoff Nr. 1.4539 Swedish Norm SS 2562 French Norm Z1NCDU 25-20 Fine Tubes Production Specification F 1090 Corrosion Resistance There is no risk of intercrystalline corrosion on cooling or welding due to the low carbon content. Pitting and crevice corrosion resistance is better than other austenitic steels due to the higher nickel and molybdenum content. The high chromium content promotes and maintains a passive film which protects the material in many corrosive environments. The general corrosion resistance, especially in sulphuric and organic acids, is good. It should be noted, however, that although it has a better resistance than other low alloy stainless steels, it has a limited use with hydrochloric acids. Metallurgical Characteristics 904L is a fully austenitic stainless steel which has greater resistance to precipitation of ferrite and sigma phases on cooling/welding than other stainless steels containing molybdenum such as 316L and 317L. Size Range for Seamless Tubing www. f i n e t u b e s . com e 103 - august 2008 904l • a high resistance to crevice corrosion • a good resistance to stress corrosion cracking • good formability and weldability Datasheet Straight Lengths Coils 48 44 40 36 34 30 26 24 22 20 16 12 9 7 4 0 0 1.6 3.2 4.8 6.4 8.0 12.7 19.0 27.0 30.0 35.0 50.8 63.5 0 1/16 1/8 3/16 1/4 5/16 1/2 3/4 1 1/16 1 3/16 1 3/8 2 2 1/2 mm ins mm wall OD ins 0.279 0.188 0.144 0.104 0.064 0.036 0.028 0.022 0.018 0.012 0.009 0.007 0.005 0.003 0.002 0 7.10 4.77 3.65 2.64 1.63 0.90 0.70 0.56 0.46 0.30 0.23 0.18 0.13 0.08 0.05 0 SWG