Test normal A36 steel and containing Ce A36Ce steel for shipbuilding (/% : 0.12-0.13C

0.21 Si

0.77-0.79Mn

0.013-0.015P

0.003-0.004S

0.32-0.33Cr

0.023-0.025Al

0-0.009Ce) are melted by vacuum induction furnace

cast to 7 kg ingot

forged to 25 mm x 25 mm billet and normalized at 865 °C for 0. 5 h. The corrosion rate

corrosion surface morphology and features of rust layer of both normal non-containing Ce A36 steel plate for shipbuilding and containing 0.009% Ce A36Ce plate for shipbuilding are analyzed by full immersion examination in simulated seawater (3. 5% NaCI) environment with using weight loss

electrochemical method

scanning electron microscope and X- ray diffractometry. Results show that in seawater for 30 day

the corrosion rate of A36 steel plate for shipbuilding is 1.8 g/ (mm

2

• day)

while that of A36Ce steel plate for shipbuilding is 1.2 g/( mm

2

• day) ； the A36Ce steel plate is easily to form denser black inner rust layer which is not easily to peel off ； the pitting corrosion tendency of nonnal A36 steel plate is more severe

but the uniform corrosion of A36Ce steel plate is primary ； the corrosion products of both steels are iron oxide and carbonyl.