JIANG Da-wei
,
GE Chang-sheng
,
ZHAO Xiang-juan
,
LI Jun
,
SHI Lu-lu
,
XIAO Xue-shan
钢铁研究学报(英文版)
A new family of economical duplex stainless steels in which N or Mn was substituted for Ni with composition of 22Cr-80Mn-xNi-10Mo-07Cu-07W-03N (x=05-20) have been developed by examining the microstructure, mechanical and corrosion properties of these alloys. The results show that these alloys have a balanced ferrite-austenite relation. In addition, the alloys are free of precipitation of sigma phase and Cr-nitride when solution-treated at 750 to 1300 ℃ for 30 min. The yield strength, tensile strength and fracture elongation values of experimental alloys solution-treated at 1050 ℃ for 30 min are about 500, 750 MPa and 400%, respectively. Low-temperature impact properties can be improved distinctly with the increase of nickel content. Among the designed DSS alloys, the alloy with Ni of 20% is found to be an optimum alloy with proper phase proportion, better low-temperature impact properties and higher pitting corrosion resistance compared with those of other alloys. The mechanical and corrosion properties and lower production cost of the designed DSSs are better than those of AISI 304.
关键词:
economical duplex stainless steel
,
low-temperature impact property
,
pitting corrosion resistance
MA Zheng-huan
,
ZHAO Xiang-juan
,
GE Chang-sheng
,
DING Tie-suo
,
LI Jun
,
XIAO Xue-shan
钢铁研究学报(英文版)
A new family of resource-saving, high chromium and manganese super duplex stainless steels (DSSs), with a composition in mass percent, % of Cr 0.29, Mn 0.12, Ni 2.0, Mo 1.0, and N 0.51-0.68, has been developed by examining the effect of N on the microstructure, mechanical properties and corrosion properties. The results show that these alloys have a balanced ferrite-austenite relation. The austenite volume fraction decreases with the solution treatment temperature, but it increases with an increase in N content. The increases in nitrogen enhance the ultimate tensile strength (UTS) and reduce the ductility of the material slightly. The pitting corrosion potential increases first and then decreases with an increase in nitrogen content when the amount of N arrives to 0.68%. The yield stress and ultimate tensile strength of solution-treated samples were more than 680 and 900 MPa, the elongation of experimental alloys are higher than 30%, respectively, what is more, the pitting potentials were beyond 1100 mV.
关键词:
duplex stainless steel
,
microstructure
,
mechanical property
,
pitting potential
