Effect by Solution Treatment on Structure and Properties of S32168 Stainless Steel Pipe

Studied are the effects by the solution treatment temperature on the structure and mechanical properties of the S32168 stainless steel.As a result it is revealed that after the solution treatment the structure of the said stainless steel is composed by equiaxed grains,and there exist annealing twins;when the solid solution temperature is≥1 080℃,the precipitates in the stainless steel are almost completely dissolved into the matrix;when the solid solution temperature is 1 040~1 120℃,the grain size grows along with the increase of the temperature,and the growth activation energy is 563.49 kJ/mol,and within this temperature range,the grain size and the room temperature mechanical properties of the S32168 stainless steel conform to the Hall-Petch relationship:the stainless steel strengthening mechanism is mainly fine grain strengthening;and along with the increase of the temperature,the fracture mode of S32168 stainless steel is transforming from the brittle fracture to the ductile fracture.