易忠烈, 陈兴润, 魏海霞, et al. Influence of Cooling Rates on Precipitated σ Phase of 2507 Super Duplex Stainless Steel[J]. Special Steel, 2023, 44(2): 17-20. DOI: 10.20057/j.1003-8620.2022-00114.
Continuous cooling test of 2507 super duplex stainless steel(/%:0.017C
6.22Ni
25.73Cr
3.39Mo
0.27N) from 1340 ℃ to room temperature by cooling rate 1-500 ℃/min has been carried out by using Gleeble 3500-GTC. The influence of cooling rate on precipitated α phase was analyzed by combining with EPMA (electro-probe macroanalyser)observation
EBSD (electro backscattering diffraction)phase analysis and thermodynamic calculation. The results show that the σ phase exists in the structure of 2507 super duplex stainless steel under the cooling rate of 1 ℃/min
and the area percentage of σ phase is 2.67%.When the cooling rate is faster than 10 ℃/min
the solidification structure is only composed of austenite and ferrite. The thermodynamic calculation results show that the smaller the cooling rate is