High temperature corrosion resistance of pack aluminized SUS316ss steel

In order to research the application of pack aluminized to the superheater in a biomass fired boiler,the aluminized layer on SUS316ss was observed and characterized by optical microscope,SEM and microhardness measurement.The corrosion resistance of the SUS316ss steel in 6%FeCl_3+0.05mol/L HCl solution and under deposition of HCl-H_2O-NaCl-KCl-NaOH-Na_2SO_4-K_2SO_4 at 500℃ was examined.The oxidation behavior of the steel at 1000℃ was also investigated.The experimental results indicate that the oxidation layer and aluminized layer of SUS316ss were dense,and thickness of the aluminized layer was 35μm,the pitting corrosion resistance of aluminized SUS316ss was better than that of unaluminized one.The oxidation properties of aluminized SUS316ss at 1000℃ increased by 5～8 times.The corrosion resistance of aluminized SUS316ss under deposition of multi-salt mixture at 500℃ increased by 7～8 times.