With magnesia and mgo-cao sand as the main raw materials,the coating material has good construction pertormance,adhesion performance,durability and disintegration performance,etc.In particular,the special treated magnesium-calcium sand is used as the coating material to effectively control the disadvantage of easy hydration of magnesium-calcium sand and ensure that the products have good construction pertormance and service performance in a long period of time.And the magnesium calcium coating material has the obvious purification function to the steel.