904L is an Austenitic Stainless Steel with high levels of Nickel (up to 2.5 times), Chromium and Molybdenum compared to 316L.  The result is a material with a very high corrosion resistance, specifically for handling medium concentrated sulfuric acid solutions and superior resistance to pitting, crevice, and stress corrosion cracking.  Yield strength is generally higher than 316L, although Ultimate Tensile Strength is comparable.

904L is non-magnetic in all conditions. 

Common Specifications: AISI 904L, ASTM A1892 A276 / A479, UNS N08904, EN 10088-3 / 10272, 1.4539, ASME SB649, PED 2014/68/EU Annex I section 4.3, AD2000 W0 (W2/W10)

NACE MR0175/ISO 15156-3 and NACE MR0103/ISO 17945.

Applications:  904L is primarily used for process equipment handling corrosive chemicals and acids in the chemical industry, and for general manufacturing equipment in the petrochemical and oil & gas industries.  It is also widely used for bleaching equipment in the pulp and paper industry and in equipment dealing with flue gas cleaning, desalination and seawater handling plants, hydrometallurgy, food and beverages, pharmaceuticals and heat exchangers.

Delivered condition: Annealed

Heat Treatment: Solution annealing at 1050°C – 1150°C followed by rapid cooling in air or water.

Size range: 12.7mm – 76.2mm

Weldability: Good weldability and excellent formability.   Low heat input is recommended.