Solution treatment of stainless steel pipes

Solution treatment of stainless steel pipes

The use of stainless steel tube is now more and more widely, because of its good corrosion resistance in engineering construction plays a vital role, in the process of production we need to carry out solution treatment of stainless steel tube, the main purpose is to obtain a certain martensite to increase the hardness of the product, let's look at the solution treatment of stainless steel tube:

(1) After solid solution treatment, it is heated to (760±15) ℃ and held at (760±15) ℃ for 90min. As Cr23C6 carbide precipitate from austenite, the content of carbon and alloying elements in the austenite 904L stainless steel tube is reduced. The Ms point is increased to 70℃ and then cooled to room temperature to obtain martensite + αferrite + residual austenite structure. The residual austenite was decomposed only after aging at 510℃.

(2) After high temperature adjustment and cryogenization, the solution was heated to 950℃ for 90min. Due to the increase of Ms point, a small amount of martensite could be obtained by cooling to room temperature; After that, a certain amount of martensite can be obtained by cold treatment at -70℃ for 8h.

(3) After solid solution treatment with cold deformation method, it is cold deformed at room temperature. During cold deformation, the number of martensite formed in 904L seamless tube is related to the deformation amount and the composition of 904L stainless steel tube.