CORROSION OF CHROMIUM STEELS IN SEAWATER

Corrosion behavior of chromium containing low alloyed steels immersed in seawater were studied; The variation of their corrosion rate with time as well as effect of chromium on seawater corrosion of the steels were analyzed. New views on “corrosion resistance reverse” of chromium steels and the effect of chromium on seawater corrosion resistance were postulated.After immesion in seawater for long time a reverse of the corrosion resistance of chromium steels do occur.Corrosion rate of carbon steels descend with immersion time.For chromium steels, the situation is opposite. Chromium debases the corrosion rate of steel in seawater at initial stage.In the meantime,it altered the corrosion character of the steel that corrosion rate of steel gradually ascend with immersion time.Accordingly, “corrosion resistance reverse” of chromium steels that immerse in seawater for long time was caused.