1. Cold rolled products have good gloss and beautiful appearance;
2. Excellent corrosion resistance, especially pitting resistance, due to the addition of Mo;
3. Excellent high-temperature strength;
4. Excellent working hardenability (weak magnetism after processing)
5. The solid solution state is non-magnetic;
6. The price is higher than 304 stainless steel.
Corrosion resistance of 904L stainless steel:
As 904L carbon content is very low (up to 0.020%), there will be no carbide precipitation in the case of general heat treatment and welding.This eliminates the risk of general heat treatment and intercrystalline corrosion after welding.Because of high chromium nickel molybdenum content and the addition of copper, 904L can be passivated even in reductive environments such as sulfuric acid and formic acid.The high nickel content makes it have low corrosion rate in the active state.In pure sulfuric acid in the range of 0~98% concentration, the service temperature of 904L can be as high as 40 degrees Celsius.The corrosion resistance of pure phosphoric acid in the range of 0~85% is very good.The corrosion resistance of impurities in phosphoric acid produced by wet process has a strong effect.Of all kinds of phosphoric acid, 904L is superior to ordinary stainless steel in corrosion resistance.In nitric acid with strong oxidization, 904L has lower corrosion resistance compared with high alloying steel without molybdenum.In hydrochloric acid, the use of 904L was limited to a lower concentration of 1-2%.In this concentration range.The corrosion resistance of 904L is better than that of conventional stainless steel.904L steel has high resistance to pitting corrosion.The resistance to crevice corrosion is also good in chloride solution.The high nickel content of 904L reduces the corrosion speed in pit and crevice.Common austenitic stainless steels may be sensitive to stress corrosion in a chloride-rich environment at temperatures above 60 degrees c, and this sensitization can be reduced by increasing the nickel content of stainless steel.Due to high nickel content, 904L has high resistance to stress corrosion cracking in chloride solution, concentrated hydroxide solution and hydrosulfide rich environment.
Scope of application
Pipeline, heat exchanger, food industry, chemical industry, etc.