Corrosion Behaviors of 16MnR Steel in Various Backfill Materials

Five kinds of materials,including Na-bentonite,Ca-bentonite,clay,magnesium oxide(MgO) and cement were selected as the backfill materials of burying containers made of 16MnR steel.The properties of the five backfill materials were determined,and the corrosion behaviors of 16MnR steel in the five backfill materials were investigated.The water content,chloride ion content and pH value of backfill materials determined the corrosion rate of 16MnR steel.The corrosion rates of 16MnR steel decreased with the increasing thickness of backfill material and were lower obviously in magnesia and cement than in Na-bentonite,Ca-bentonite and clay.Especially,the corrosion rate of 16MnR steel buried in magnesia or cement was about tenth in Na-bentonite,Ca-bentonite or clay.The corrosion rate of 16MnR steel was less than the atmosphere corrosion rate of 16 MnR steel hung in the cavern,when the thickness of magnesia or cement was more than 5 cm,or thickness of Na-bentonite,Ca-bentonite or clay was more than 12 cm.