The properties of surface passivating film of cold rolled stainless steel 409L(%:0.017C
11.50Cr
0. 17Ti) passivated in 20%HNO
3
solution at 58 ℃ for 0~60 min have been analyzed by using glow discharge emission spectrometry (GDS)
scanning electron microscope(SEM)and X-ray photoelectron spectroscopy(XPS)
and the effect of passivating film thickness on its corrosion resistance has been got by salt spray test.Results showed that with passivating for 10 min
the passivating film thickness was up to maximum 48 nm;and with passivating for 3 min
the passivating film thickness was 40 nm;the surface nitrides of sample were completely covered by passivating film and the content of chromium oxide was most with best corrosion resistance.