904L filter cartridge is made of 904L perforated plate and multilayer 904L wire mesh after sintering or multilayer 904L wire mesh after sintering, and it is made of high-precision welding process. It can be customized according to different purposes and working environment. Excellent corrosion resistance, good corrosion resistance in non oxidizing acids such as sulfuric acid, acetic acid, formic acid and phosphoric acid, good resistance to pitting corrosion in neutral chloride ion medium, and good resistance to crevice corrosion and stress corrosion. It is suitable for sulfuric acid of various concentrations below 70 ℃, and it can resist any concentration and temperature of acetic acid under normal pressure, and the corrosion resistance of the mixed acid of formic acid and acetic acid is also very good. It has high chromium content and enough nickel content. The addition of copper makes it have strong acid resistance, especially high resistance to chloride gap corrosion and stress corrosion cracking. It is not easy to appear corrosion spots and cracks. Its resistance to pitting is slightly better than other steel grades. It has good processability and weldability and can be used in pressure vessels.