CORROSION BEHAVIOR AND VARIATION OF APPARENT MECHANICAL PROPERTY OF ONE NEWLY-DEVELOPED LOW CARBON BAINITIC STEEL IN ENVIRONMENT CONTAINING CHLORIDE ION

The corrosion resistance of one newly-developed low carbon bainitic steel, ultra-low carbon ferritic steel and 09CuPCrNi steel was researched in environment containing chloride ions through alternate wet-dry accelerated corrosion test. The bainitic steel possesses both excellent mechanical property and excellent corrosion resistance. The corrosion rate of the bainitic steel was obviously lower than that of the other two steels and the gap increased with corrosion time. The phase constituents of the rust layers of the three kinds of steel were similar, while corrosion products of the bainitic steel were finest and most compact. The enrichment of Cr and Cu in the rust layer near the matrix of the bainitic steel was most obvious, while the content of chloride was lowest in the same location. The ability of rust layer in the bainitic steel to block permeation of chloride ion was higher than that of the two other steel.