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Effect of nitrogen content on the microstructure and erosion-corrosion (E-C) behavior of stainless steel (containing about 25%Cr,5%-6%Ni,and 1%-2%Mo) was investigated by using optical microscope(OM),potentiodynamic polarization curve and immersion method,a self-made rotating disk apparatus and scanning electron microscopy (SEM) and so on. The results show that with the increase of nitrogen content from 0 (no adding) to 0.485 wt.%,the Creq/Nieq ratio of the tested materials decreases from 4.14 to 1.23 and the ferrite volume percentage of the steel tested linearly decreases approximately from 90% to 10%. The effect of nitrogen content on polarization behavior of the studied steel was not signifi cant. All the passive current densities ( Ip) and pure corrosion rates (Vc) of the different N content specimens in the acidic solution (slurry containing 0.1 M H2SO4+0.06%Cl-+0.4%F-,the simplified zinc hydrometallurgy slurry) are too low and nearly negligible. Whereas the pure erosion rates (Ve ) of the four scenarios of the steels tested (N content,wt.%:N1,no adding; N2,0.143%; N3,0.289%; N4,0485%,respectively) are much higher than their Vc values. The V e values of the tested steels are in the order of N4 > N1 > N3 > N2,at the same time,the total weight loss rates (V t ) follow the order of N4 > N1 >N3 > N2,too. N2 steel consisting of approximately equal volume fractions of ferrite (α) and austenite (c) exhibits the most excellent E-C resistance and erosion resistance,while the stainless steels possessing the big difference between α phase and c phase,such as N1 steel nearly possessing single ferrite or N4 steel nearly possessing single austenite,show poorer E-C resistance and erosion resistance.
Effect of nitrogen content on the microstructure and erosion-corrosion (EC) behavior of stainless steel (containing about 25% Cr, 5% -6% Ni, and 1% -2% Mo) was investigated by using optical microscope potentiodynamic polarization curve and immersion method, a self-made rotating disk apparatus and scanning electron microscopy (SEM) and so on. The results show that with the increase of nitrogen content from 0 (no adding) to 0.485 wt.%, the Creq / Nieq ratio of the tested materials decreased from 4.14 to 1.23 and the ferrite volume percentage of the steel tested linearly reduced from about from 90% to 10%. The effect of nitrogen content on polarization behavior of the studied steel was not signifi cant. current densities (Ip) and pure corrosion rates (Vc) of the different N content specimens in the acidic solution (slurry containing 0.1 M H2SO4 + 0.06% Cl- + 0.4% F-, the simplified zinc hydrometallurgy slurry) are too low and nearly Negligible. Whereas the pure erosion rates (Ve ) of the four scenarios of the steels tested (N content, wt.%: N1, no adding; N2,0.143%; N3,0.289%; N4,0485%, respectively) are much higher than their Vc values. The V e values of the tested steels are in the order of N4> N1> N3> N2, at the same time, the total weight loss rates (V t) follow the order of N4> N1> N3> N2, too. approximately equal volume fractions of ferrite (α) and austenite (c) exhibits the most excellent EC resistance and erosion resistance, while the stainless steels possessing the big difference between α phase and c phase, such as N1 steel was possession single ferrite or N4 steel nearly possessing single austenite, show poorer EC resistance and erosion resistance.