904L Austenitic Stainless Steel Round Bar

904L super austenitic stainless steel is a low carbon, high nickel, molybdenum austenitic stainless and acid resistant steel. It is a proprietary material introduced from French h · s company. It has good activation passivation transformation ability, excellent corrosion resistance, good corrosion resistance in non oxidizing acids such as sulfuric acid, acetic acid, formic acid and phosphoric acid, good pitting corrosion resistance in neutral chloride ion containing medium, and good crack corrosion resistance and stress corrosion resistance. It is suitable for various concentrations of sulfuric acid below 70 ℃. It is also resistant to acetic acid of any concentration and temperature under normal pressure and the mixed acid of formic acid and acetic acid.

Super austenitic stainless steel 904L (00cr20ni25mo4.5cu; UNS: N08904; en: 1.4539) is a high alloy austenitic stainless steel with low carbon content. It has good corrosion resistance in dilute sulfuric acid and is designed for harsh corrosion conditions. It has high chromium content and sufficient nickel content. The addition of copper makes it have strong acid resistance, especially high resistance to chloride interstitial corrosion and stress corrosion cracking, less prone to corrosion spots and cracks, slightly better anti pitting ability than other steel grades, good machinability and weldability, and can be used in pressure vessels.

Brand and standard:

UNS N08904 (standard jointly designed by the American Society of automotive engineers and the American Society for testing and materials in 1967), din1 4539 (German standard), ASTM a240 (American Society for testing and materials standard; it is classified as stainless steel series in the new standard and nickel base alloy series in the original standard ASME sb-625), sus890l.

Physical and mechanical properties:

904L steel has high pitting corrosion resistance. In chloride solution, its anti crevice corrosion ability is also very good. The high nickel content of 904L reduces the corrosion rate in pits and cracks. When the temperature of ordinary austenitic stainless steel is higher than 60 ℃, it may be sensitive to stress corrosion in a chloride rich environment. This sensitivity can be reduced by increasing the nickel content of stainless steel. Due to the high nickel content, 904L has high resistance to stress corrosion cracking in chloride solution, concentrated hydroxide solution and hydrogen sulfide rich environment.