LOW TEMPERATURE HOT CORROSION RESISTANCE OF ALUMINIZED AND CHROMIZED COMMERCIAL IRON
渗铝、渗铬工业纯铁的耐低温热腐蚀性能

Pack cementation and hot dipping processes were respectively employed to prepare aluminide coatings on commercial iron.Commercial iron was also chromized by means of pack cementarion.The low temperature hot corrosion behavior of aluminized and chromized commercial iron was studied in the pres- ence of a thin film of K_2SO_4-Na_2SO_4 on the coating surface.Experimental results indicate that aluminized commercial iron is still subject to this type of hot corrosion due to the formation of a liquid complex sulfate phase containing K,Na,Al and Fe.Chromized commercial iron has shown excellent corrosion resistance, which is attributed to the rapid growth of a continuous Cr_2O_3-rich oxide film on the coating surface.On this basis it can be concluded that chromizing is effective in the LTHC protection of iron-based alloys.